and Structure of the Proteus Anguinus. 17 



was, therefore, fastened on a board, the abdomen was opened^ 

 and its walls kept asunder by means of pins, in order to observe 

 what would happen to the air-bladders. In a few minutes the 

 animal began to take air into the mouth, and afterwards panted 

 with a quickness always increasing for a quarter of an hour ; 

 after which his pantings became weaker, and at the end of half 

 an hour he died. While the proteus was thus agitated and 

 panting, they watched attentively the two air-bladders, but did 

 not see in them the smallest movement, which could indicate 

 the entrance of air. They saw, however, that these bladders 

 gradually contracted from the action of the external air; and at 

 length became corrugated to such a degree, as to resemble in 

 figure two fleshy bodies, of the form and size of two grains 

 of wheat. The air which entered the mouth escaped entirely 

 by the branchial apertures, forming mostly minute bubbles, 

 which, for some time, remained attached to the edges of those 

 apertures. 



7. Of the Organs of Generation. 



The authors regret, that, under this head, their observations 

 are not so complete as they could have wished ; and that some 

 points relating to it are still enveloped in obscurity. 



Of the five protei dissected in the month of May, as before 

 stated, there were two in whom the sexual organs were so fully 

 developed, that no doubt could remain of the one being a male, 

 and the other a female. In the male, the testes were attached to the 

 air-bladder. To the eye they appeared to be a congeries of most 

 minute globules; but when examined under the microscope, 

 their substance was nothing; else than a mass of most minute 

 vessels, disposed longitudinally, and extending in a serpentine 

 line from one end of the testicle to the other. Towards the 

 posterior part of the organ, where it had somewhat of a pyri- 

 form figure, these minute vessels enlarged and separated a little 

 from ecah other. Continuing the examination, they observed, 

 towards the extremity of the alimentary canal, a circular ring, 

 evidently formed by the internal tunic of the intestine, from 

 which proceeded many longitudinal threads, which extended to 

 the margin of the anus : but nothing was seen like a receptacle 

 for semen, nor penis, nor vasa deferentia. A vessel seemed to 

 extend from the posterior part of the testicle, and open into the 



