American spiders and their spinningworkA natural history of the orbweaving spiders of the United States, with special regard to their industry and habits . ermatozoa werearranged singly above the threads. Immediately after the spider was secured, one of its palps was vesiculum seminis was charged with spermatozoa, even to the embolos,where they were plainly seen at intervals. He could not, however, discoverany on the external parts of the palpus. Menge is entitled to the creditof discovering the relation between the male palpus and the male abdom-inal sexual organ. 1 Ausserer confi
American spiders and their spinningworkA natural history of the orbweaving spiders of the United States, with special regard to their industry and habits . ermatozoa werearranged singly above the threads. Immediately after the spider was secured, one of its palps was vesiculum seminis was charged with spermatozoa, even to the embolos,where they were plainly seen at intervals. He could not, however, discoverany on the external parts of the palpus. Menge is entitled to the creditof discovering the relation between the male palpus and the male abdom-inal sexual organ. 1 Ausserer confirmed the observations of Menge in studies of Linyphiatriangularis and Dictyna benigna.^ Bertkau, following the same line ofinvestigation with Linyphia montana and anotherspecies, corroborated these statements.* In the act of copulation Blackwall observed, whatI have recorded of Linyphia marginata, that thepalps were frequently conveyed to the mouth. Hesaw a male Lycosa lugubrius apply his palps eightytimes to the vulva of the female withoutApplica- (j-jg possibility of bringing it into contactwith the inferior surface of its abdomen Palps. A>Ji^ except by a very conspicuous change of As an equal number of similar acts wasperformed by the left palp, we have the extraor-dinary fact of the palps being employed one hun-dred and sixty times during this greatly i^rotractedprocess, unaccompanied by any contact whatever with the part where theseminal ducts are considered to terminate.* Fig. 37. Spermatozoa of Teg-enaria. X 570. (After Camp-bell.) VI. Whether or not spiders may be propagated by agamic reproduction is an open question. I am at least satisfied that females will 2)roduce cocoons without })revious pairing with the male. It is reasonably certain, Agamic jjgQ^ ^ly^^ jj-^ gQuie species a single act of fecundation suffices for du t ^^^ ^^^ ^S^s Is-ic^ foi several years in succession, where life is continued that long. Audebert brought up and kept for some / years
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectspiders, bookyear1890
