LOPHOSTEUS SUPERBUS PANDER: ZÄHNE, ZAHNKNOCHEN UND BESONDERE SCHUPPENFORMEN

Morphological and histological studies of numerous remains of Lophosteus superbus Pander from erratic boulders of Beyrichia Limestone prove that the peculiar teeth recently brought to notice by Gross (1969) belong to Lophosteus and are not of acanthodian origin. The structure of these teeth as well as that of some tooth-bearing bones and scales is described. The investigation was extended to cover the teeth of smaller Devonian actinopterygians and cross-opterygians to establish whether Lophosteus is an actinopterygian, a crossopterygian, or even a member of a hitherto unknown group of Osteichthyes. Results unfortunately proved negative, as the very small teeth of various species offer too few distinct and symptomatic histological characteristics. A solution of this question must await the discovery of determinable skull and lower jaw bones of the genus Lophosteus.
Die morphologische und histologische LTntersuchung zahlreicher in nordwest-deutschen Geschieben des Beyrichienkalkes gefundener Reste von Lophosteus superbus Pander beweist, daß die kürzlich von Gross (1969) erwähnten, eigenartigen und nicht von Acanthodiern stammenden Zähne zu Lophosteus gehören. Der Bau der Zähne und einiger Zahnknochen und Schuppen wird beschrieben. Um die Fragen zu klaren, ob Lophosteus zu den Actinopterygiern oder zu den Crossopterygiern gehört oder gar zu einer bisher unbekannten Gruppe der Osteichthyes, wurde die Untersuchung auch auf die Zähne kleiner devonischer Actinopterygier und Crossopterygier ausgedehnt. Das Ergebnis war leider negativ: die sehr kleinen Zähne der verschiedenen untersuchten Arten bieten zu wenig kennzeichnende und unterscheidende histologische Merkmale. Nur von der Entdeckung bestimmbarer Schädel- und Unterkiefer-Knochen der Gattung Lophosteus kann die Entscheidung dieser Frage erhofft werden.     

Glutamine synthesis in germinating seeds of Cucurbita moschata

During germination, an increase in glutamine and glutamine synthetase[L-glutamate: ammonia ligase (ADP), EC 6.3.1.2 [EC] ] occurred inthe cotyledons reaching a maximum at 4 to 6 days. The enzymehad a Km of 4.5 nun for L-glutamate, and 0.67 mu for hydroxylamine.Hydroxylamine exhibited substrate inhibition kinetics. The enzymewas inhibited by calcium ion, fluoride ion and p-hydroxymercuribenzoatebut not by EDTA, sodium ion or chloride ion. The sulf hydrylinhibition was reversed by dithiothreitol. In vivo synthesisof glutamine-¹⁴C from glutamate-¹⁴C was found to parallel theincrease in glutamine content and the in vitro glutamine synthetaseactivity during germination. ¹ Present address: Department of Biology, Mercyhurst College,Erie, Pennsylvania 16501, U.S.A. (Received June 12, 1971; )     

Über das Gebiss der Acanthodier und Placodermen

In their dentition, acanthodians and placoderms differ from other fishes by the ontogenetie development and replacement of their teeth and by the histology of the functional elements (teeth, cutting edges of the jaws). In some cases special diets are indicated. In general, however, their dentition seems to have been less effective than that of elasmobranchs and teleostomes. This fact may partly account for their early extinction.
Die Eigenart des Gebisses der Aoanthodier und Placodermen inbezug auf die Zahnbildung (Ontogenese), den Zahnersatz und den histologischen Bau der funktionalen Elemente (Zähne, Schneidekanten des Kieferknochens) wird dargestellt. Aus dem Bau des Gebisses läßt sich die Nahrung dieser Tiere teilweise erschließen. Das eigenartige Gebiß verursaehte vermutlich eine Konkurrenzunterlegenheit beim Nahrungserwerb gegenüber den Elasmobranchiern und Teleostomen, vielleicht einer der Gründe, der zum frühen Aussterben der Acanthodier und Placodermen führte.     

Thrips see red – flower colour and the host relationships of a polyphagous anthophilic thrips

Abstract 1. The common blossom thrips, Frankliniella schultzei, is a polyphagous anthophilic species that colonises a wide range of host‐plant species across different plant taxa. The environmental cues used by these polyphagous insects to recognise and locate host plants are not known. We therefore determined if colour is an important environmental signal used by F. schultzei to recognise flowers of eight of its more significant host‐plant species. 2. The effect of flower colour on the colonisation of different host plant species by F. schultzei was investigated by collecting and analysing the following: (a) numbers of thrips from different heights and aspects of the primary host plant Malvaviscus arboreus, (b) thrips distribution within flowers of Hibiscus rosasinensis, (c) colour reflectance from flowers of eight different host‐plant species, and (d) reflectance from different coloured sticky traps and the number of thrips trapped on them at different times of the day and on different dates. 3. The results indicate that: (a) the thrips (both sexes) concentrate towards the top of the primary host plant M. arboreus and are not distributed differentially according to sunny or shady aspect of the plant, (b) the number of female thrips on H. rosasinensis was higher in anthers compared to petals (corolla) and the basal parts of the flower, and males were as numerous on the petals as were females, and (c) there is a common floral reflectance pattern (but with different intensities) across the eight host plant species, mainly in the red part of the spectrum (600–700 nm). 4. Results of colour sticky trapping show that red attracts more female thrips compared to any other colour and that most were caught between 09.00 and 11.00 hours. By contrast, more male thrips were trapped between 07.00 and 09.00 hours. Males were more evenly distributed across the different colours but the highest numbers were associated with the yellow traps. 5. The higher densities of thrips at the top of their host plant may be related to the early morning (07.00–11.00 hours) activity of the thrips, when the top portions of the plant are more exposed to sunlight. The sex‐related distributions of F. schultzei thrips across time, coloured sticky traps, and various parts of the flowers seem to be related to mating swarm formation by the males, on the one hand, and the relative frequency and intensity of the use of M. arboreus by the females, on the other, as a feeding and oviposition site. Frankliniella schultzei females respond more strongly to red than to any other colours, so it is predicted that the spectral properties of colour recognition by this species will correlate with the predominant red reflectance of its primary host, M. arboreus, and that there may well be a sex‐related difference in colour recognition within this species.     

BRAIN,MIND AND MACHINE: WHAT ARE THE IMPLICATIONS OF DEEP BRAIN STIMULATION FOR PERCEPTIONS OF PERSONAL IDENTITY,AGENCY AND FREE WILL?

Brain implants, such as Deep Brain Stimulation (DBS), which are designed to improve motor, mood and behavioural pathology, present unique challenges to our understanding of identity, agency and free will. This is because these devices can have visible effects on persons' physical and psychological properties yet are essentially undetectable when operating correctly. They can supplement and compensate for one's inherent abilities and faculties when they are compromised by neuropsychiatric disorders. Further, unlike talk therapy or pharmacological treatments, patients need not ‘do’ anything for the treatment to take effect. If one accepts, as we argue here, that brain implants are unique among implantable types of devices, then this can have significant implications for what it means to persist as the same person and be the source of one's thoughts and actions. By examining two of the most common indications for DBS in current use, namely in the motor (Parkinson's Disease) and psychiatric (Major Depression) domains, we further argue that although DBS, as it is currently applied, does not necessarily represent a unique threat to personal identity and agency per se, it introduces an unprecedented ‘third party’ into the debate on these concepts. In this way, DBS can be used as a tool to begin probing, both conceptually and empirically, some of philosophy's most perennial metaphysical questions.     

The distribution and persistence of iprodione applied by thermal fogging in a glasshouse tomato crop

Deposits collected on filter paper after application of a ready-to-fog formulation of iprodione and the residues of iprodione washed from tomato leaves after fog and HV spray application were analysed by gas-liquid-chromatography. Relatively heavy deposits were found close to the fogging machine but the deposit became lighter with increasing distance from the machine and in positions lateral to the stream of fog. The deposit collected within the leaf canopy was considerably lighter than that collected above the plants. Residues of iprodione on plants treated with HV sprays were always considerably higher than on fogged plants given a comparable rate of application. After repeated treatment, a substantial build-up of residue was found, but the amount on fogged plants was approximately half that on plants treated with HV sprays. There was a good correlation between the residue found on plants at six positions within the glasshouses and the incidence of infection from artificial inoculations of Botrytis cinerea on petioles.