PULMONARliE. 
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 figiire 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 temperature 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 developement and that of the foetus, see the admirable work of 
Herold. 
•t See Treviranus, on the same subject. 
