ON ARACHNIDA. 481 



the precaution of closing the aperture exactly, and it is pro- 

 bable that many other species are similarly prudent. 



The lycosas, especially such as frequent the neighbour- 

 hood of aquatic places, begin to be found from the earliest 

 fine days of spring. Coupling takes place, according to the 

 species and the temperature of the Aveather, from the month 

 of May to the middle of July. The eggs are free, usually 

 spherical, and their number varies according to the species, 

 being sometimes twenty, seventy, eighty, and even one hun- 

 dred and eighty. They are enclosed in a sac or cocoon, 

 sometimes globular, sometimes flatted, circular, and formed by 

 two caps united at their edges. It is membranaceous, and 

 composed of a compact silk. Clerk has observed some 

 which were whitish above, and blackish underneath. The 

 cocoon of the Lycosa littoralis, one of those whose figure is 

 lenticular, is grey externally, with a white circle, and formed 

 of a less compact silk ; its interior parietes are whitish ; the egg- 

 sac is always attached to the hinder part of the female by means 

 of a small pellet, or silken tie, issuing from the spinnerets ; she 

 applies the threads over its surface, causing to act upon it 

 wath rapidity, the nipples, which are the conduits of the silk. 

 If we detach this sac, we unwind, at the same time, a thread 

 of silk which issues from the spinneret. Lister has even 

 maintained that the animal can withdraw this sac into the 

 interior of its spinnerets, which Degeer conceives to be im- 

 possible. The female always carries this precious deposit 

 along with her, and in spite of her burthen, runs with celerity. 

 If she is separated from it, she testifies her uneasiness by 

 running to and fro on all sides, and as soon as she has found 

 it, she seizes and runs off with it. Clerk tells us, with re- 

 spect to the species which he names Ainentatus, that when 

 she has recovered her cocoon, she carries it at first, putting it 

 under the belly, and approached a little to one side of the 



VOL. XIII. I 1 



