Arrangement of sperm within the spermatheca of fleas, with remarks on sperm displacement

The arrangement of sperm within the spermatheca of the impregnated rabbit flea is described. The numerical superiority of the sperm injections from the numerous later matings suggests that a modified form of sperm displacement probably occurs in this species.     

Cannabis sativa: volatile compounds from pollen and entire male and female plants of two variants, Northern Lights and Hawaian Indica

Sixty-eight compounds were identified by coupled gas chromatography and mass spectrometry (GC-MS) in the chemosphere of Cannabis sativa L. pollen and entire male and female plants of two cultivated varieties, Northern Lights and Hawaian Indica. Twenty-one and 28 substances, respectively, were present in pollen of the two forms. To conserve the natural composition of volatiles a delicate headspace method was employed. The two varieties represent different chemotypes which distinguish themselves, in the main quantitatively, in the setup of volatiles from pollen and entire male and female plants. Twenty compounds were monoterpenes, including the five major components: β-myrcene (E)-β-ocimene, terpinolene, β-pinene and limonene; 25 were sesquiterpenes, and the other 23 were of mixed biogenetic origin, including 3-methyl-1-butanol and benzylalcohol which occurred only in pollen; two pyrazines occurred only in Northern Lights females. Besides being of interest in natural products chemistry, the results should have relevance for plant systematics and for the pharmaceutical and technical applications of Cannabis . We demonstrate that the pollen has a distinct chemical character in possessing two exclusive volatiles, while lacking seven compounds occurring in males and females of both variants.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 147 , 387–397.