PULMONARI/B. 281 



four, a sort of fold or annular vestige found even in those where 

 there are but two, and placed directly behind them, forms a line that 

 separates the two pairs, 



The females have two very distinct ovaries, lodged in a species of 

 capsule formed by the liver. In an unfecundated state they appear 

 to be composed of a spongy, flaky kind of tissue, formed by the 

 agglomeration of rounded and scarcely visible corpuscles, which are 

 the germs of eggs. As the results of fecundation become more 

 apparent, the cluster formed by these ova * becomes less compact, and 

 they are seen to be laterally inserted on several canals. Their great 

 analogy to the ovarier of the Scorpions induces the same observer to 

 presume that they form meshes terminating in two distinct oviducts, 

 which open into a common vulva. The figure of the latter varies ; 

 sometimes it is a longitudinal bilabiated slit, as in the Micrommata 

 argelasia ; sometimes it is protected by an elongated operculum with 

 a caudiform termination, as in the Epeira diadema ; and at others 

 resembles a tubercle. 



With respect to the simple eyes, or ocelli, he remarks that they 

 shine in darkness like those of Cats, and that the Araneides most 

 probably enjoy the faculty both of nocturnal and diurnal vision. 



The abdomen becomes so putrid and decomposed after death, that 

 its colours and even its form are soon destroyed. M. Dufour, by 

 means of a rapid desiccation, the mode of which he points out, has 

 succeeded in remedying this evil to a great degree. 



The silk, according to Reaumur, is first elaborated in two little 

 reservoirs, shaped like tears of glass, placed obliquely, one on each 

 side, at the base of six other reservoirs, resembling intestines, situated 

 close to each other, flexed six or seven times, proceeding from a 

 little vessel beneath the origin of the abdomen, and terminating in the 

 papillae by a very slender thread. It is in these last mentioned vessels 

 that the silk acquires a greater degree of firmness and other proper- 

 ties peculiar to it ; they communicate with the preceding ones by 

 branches, forming a number of geniculate turns, and then various 

 pieces of net-work f- The newly spun filaments, when first drawn 

 from the mammillae, are adhesive, and a certain degree of desiccation 

 or evaporation is required to fit them for their destined purposes. 

 When the tempi rat ure is propitious, however, a single instant is 

 sufficient, as the animal employs them the moment they escape from 

 the apparatus. Those white and silky flocculi that may be observed 



* For their dcvelopemcnt and that of the foetus, see the admirable work of 

 ll.rold. 

 t See Trcviranus, on the same subject. 



