ORDKR PULMOtfARLE. 
389 
appears to consist but of a simple dorsal vessel, and also rela- 
tively to the testicles and the spermatic vessels, on which he 
has afforded no information. 
The dorsal region of the abdomen in many araneides, espe- 
cially in those which are smooth or but slightly furnished with 
hair, presents deep or umbilical points, the number and dis- 
position of which vary. M. Dufour has ascertained that those 
little orbicular depressions were determined by the attach- 
ment of the filiform muscles which traverse the liver, and 
which he has also observed in the scorpions. 
The pulmonary cavities, to the number of one or two pair, 
are indicated externally by so man} 7 yellowish or whitish 
spots, placed near the base of the belly, immediately after the 
segment, which, by means of a fleshy thread, unites the abdo- 
men with the thorax. Each pulmonary pouch is formed by 
the superposition of a great number of triangular leaflets, 
white, and extremely slender, w T hich meet together around the 
stigmata, which always answer in number to the pulmonary 
sacs. Where there are four of them, a sort of fold, or vestige 
of a ring, existing even in those where there are but two, and 
placed immediately after them, forms a line, which separates 
the two pairs. 
The female araneides have two very distinct ovaries, lodged 
in a sort of capsule formed by the liver. Not fecundated, they 
appear of a spongy tissue, as it w r ere flaky, and constituted 
by the agglomeration of rounded corpuscles, scarcely percep- 
tible, which are the germs of the eggs. In proportion to the 
progress of fecundation, the cluster formed by these eggs 
becomes less compact; and we find that they are inserted 
laterally on many canals. Their great analogy with the 
ovaries of the scorpion causes the same observer to presume 
that they form meshes, terminating in two distinct oviducts, 
which open into one and the same vulva. The configuration 
of the latter varies much : sometimes it is a longitudinal bila- 
