SPERMIOGENESIS IN BARNACLES WITH SPECIAL REFERENCE TO ORGANIZATION OF THE ACCESSORY BODY*

Ultrastructural changes during spermiogenesis in the barnacles, Balanus amphitrite albicostatus, Balanus tintinnabulum rosa, Balanus trigonus and Tetraclita squamosa japonica, and organization of the sperm with special reference to the accessory body were studied. The Golgi complex organizes both the acrosome and the accessory body at different stages during spermiogenesis; the former is formed at the mid-spermatid stage and the latter is formed at the late spermatid stage. The arrangement of the components in the mature filiform sperm is quite unique, with the acrosome, the basal body just behind the acrosome, the axial filament parallel to a long nucleus, and a slender long mitochondrion behind the nucleus. The sperm in the anterior and posterior half of the ejaculatory duct differ from each other in form in that the sperm in the anterior duct are not equipped with the accessory body and the sperm in the posterior duct are. The accessory body can be artificially broken down by some treatments (1 M urea, alkaline sea water: pH 9.0-9.7, low ionic concentration of sea water). The loss of the accessory body from the sperm is assumed to be related to the ferti-lizability of the sperm.     

Oogenesis in a Flesh Fly, Sarcophaga ruficornis

Maturation of the oocyte in the polytrophic ovariole of the flesh fly, Sarcophaga ruficornis was subdivided into 12 growing stages. The nurse cells increasing in volume during initial stages 1–6, shrink sharply in size from stage 7 onwards and finally disintegrate in stage 12. The oocyte continues to increase in volume till it reaches 1.2×107⁷μ³ in stage 12 before ovulation. The onset of vitellogenesis is marked by the appearance of protein-containing granules in the peripheral ooplasm in stage 7. The follicular epithelial cells around the oocyte exhibit changes in their shape in different stages and perhaps facilitate as well as stop the transport of yolk precursors to the ooplasm. Finally, after the formation of egg membranes around the yolk-filled oocyte, the follicular epithelium is sloughed off in stage 12.     

Pteromalid parasitoids (Hymenoptera) of Oulema oryzae (Kuwayama) (Coleoptera: Chrysomelidae) from Japan, with notes on Pteromalus bifoveolatus

The present paper discusses three Japanese species of Pteromalidae reared from cocoons of the rice beetle Oulema oryzae (Kuwayama, 1929) (Coleoptera, Chrysomelidae). Pteromalus cyclostomus Ishizaki sp. nov. is described. Spaniopus monospilus (Thomson, 1878) and Usubaia liparae Kamijo, 1983 are newly recognized as parasitoid wasps of O. oryzae , and the former is also recorded from Japan for the first time. Pteromalus bifoveolatus Förster, 1861 is also newly recorded from Japan, with a new host record from Samia cynthia pryeri (Lepidoptera: Saturniidae).     

First record of the emesine assassin bug genus Emesopsis (Heteroptera: Reduviidae) from Vietnam, with descriptions of two new species

The emesine assassin bug genus Emesopsis is reported from Vietnam for the first time and is briefly diagnosed, and two new species of the genus, E. longipilosa and E. albispinosa, are described. They were collected by beating dead, drooping leaves of the banana, Musa acuminata (Musaceae).     

Leishmaniasis in Brazil. XXV. Sandfly vectors of Leishmania in Pará State, Brazil

Leishmania of the braziliensis complex were isolated from various members of the squamiventris series sandflies, including Psychodopygus chagasi (Costa Lima), P.s.maripaensis (Ready et al.), P.s.squamiventris (Lutz & Neiva), and also P.ayrozai (Barreto & Coutinho) and Lutzomyia umbratilis Ward & Fraiha. Three different serodemes of Le.b.guyanensis Floch were isolated from Lu.anduzei Rozeboom, Lu.umbratilis and Lu.whitmani Antunes & Coutinho, simultaneously captured in the same area. Unidentified Leishmania were isolated from P.claustrei Abonnenc et al., and trypanosomes from Lu.pinottii Damasceno & Arouck and an unidentified species of Lutzomyia. A naturally infected female P.s.maripaensis transmitted a braziliensis complex Leishmania, by bite, to a hamster.     

Fish Tumor Pigment Cells: Differentiation and Comparison to Their Normal Counterparts

The objectives of this paper are to describe 1) the developmentof new research systems for biochemical comparison of cellulartraits between normal and tumorous pigment cells of fish origin,2) the similarity and dissimilarity between these two categoriesof pigment cells with regard to growth, differentiation andpigment translocating activities and 3) the potentials of thesetumorous pigment cells to manifest multiple differentiation.The development of research systems has been achieved by theestablishment of 1) methods to obtain homogenous populationsof viable, cultivatable xanthophores (erythrophores) and melanophoresfrom goldfish skins, 2) permanent cell lines from goldfish erythrophoromas(tumors derived from erythrophores) and from Nibe croaker irido-melanophoromas(tumors composed of mixed populations of iridophore- and melanophore-likecells) and 3) procedures to induce differentiation in normaland tumorous stem cells (including the formation of pigmentsand ability to undergo pigment translocation in response tocAMP, to the neurotransmitter epinephrine and to the hormonesACTH and melatonin). Two kinds of tumorous pigment cell linesexamined herein have the ability to form, in addition to variouspigments, structures similar to dermal skeletons and lentoidbodies. These findings strongly suggest the possibility thatthese fish pigment cell tumors are neural crest stem cell tumorsin nature.     

CHANGES IN THE ACTIVITY OF ACID PHOSPHATASE AND THE APPEARANCE OF METAMORPHOSING POTENCIES OF THE LARVAE OF THE ASCIDIAN, HALOCYNTHIA RORETZI

In the swimming phase of the larvae of the ascidian, Halocynthia roretzi , changes in the activity of acid phosphatase (AcP-ase) were studied cytochemically with respect to the appearance of metamorphosing potencies. The AcP-ase activity in the larvae before and soon after hatching is weakly visible only in and around the nuclei of the epithelial, muscular and notochordal cells. 6 hr after hatching the enzyme activity begins t o appear weakly in the microblasts around the proximal end of the notochordal sheath, whereas the activities which were found in the previous stages disappear. In the larvae which passed for 12 hr after hatching, the activity of AcP-ase is distinctly shown in the microblasts and also in the other 2 mesodermal cells, meso- and macro- blasts. The microblasts of this stage are closely attached to the notochordal sheath at the proximal end. At the same time, many large granules which appear similar to lysosomes are found in the microblast by an electron microscopy. The 6th hour's larvae after hatching can be induced slowly to resorb its tail by the treatment with a nile blue solution, but the time which it takes for tail resorption is gradually shortened depending on the age of the larva up until 12 hr after hatching.
From these results, i t was concluded that the appearance of the AcP-ase activity in the microblasts was parallel with the appearance of the potency of metamorphosis of the larvae after hatching. Possible roles of the microblasts at onset of meta- morphosis would seem to play a role in the rupture of the notochordal sheath and in the succeeding regression of the tail tissues.