PIPA MONSTROSA. 379 



enveloped in the transparent gelatinous part ; then they pass into the 

 last turn of the ducts, which is enlarged ; from thence they are thrown 

 into the rectum, the two ducts communicating before they enter the 

 rectum [cloaca]. This gelatinous matter is, as it were, spun out of the 

 general reservoir, having the ova in its centre. I suspect that the two 

 oviducts spin alternately, because one oviduct was empty while the 

 other was nearly full 1 . 



The stomach and whole intestinal canal of a toad is just the same 

 with the ' Savage of the Wood,' which is of the lizard kind (which 

 see) 2 . 



The Frog \Rana temporaria, Linn.] . 



Frogs have their eggs taken up as in the toad. In some which I 

 examined, which had been deprived of the male, I found that the ova- 

 rium on the right side was quite empty of ripe eggs, and also none in 

 that duct ; the ovarium of the left side was almost empty. There was 

 an opening in that ovarium where they had made their escape. The 

 oviduct was filled with ova, each of which was surrounded with its 

 jelly, which stuck to its neighbour by contact. The fimbriae had con- 

 tinued to absorb till the duct could not contain any more ; so that it had 

 burst ; and, the absorption still taking place, they had made their 

 escape out of the duct into the cavity of the belly. The ova, so 

 absorbed, are carried along the oviduct to its reservoir : in their passage 

 they are surrounded by the transparent mucus, each ovum having a 

 distinct circumscribed substance to itself. 



These ova get into the last and largest part of the oviduct, where 

 they are ready to be thrown out when stimulated by the male ; when 

 they are thrown out, they can only come singly, or in pairs at most. 

 By the stickiness of the transparent part they form themselves into a 

 large cluster, and in this procedure they unite with or take into their 

 interstices, small globules of air, which make them somewhat lighter 

 than the water they swim in. 



Prog's, toads, newts, &c, all leave the water in the winter; for, 

 although the water may be as warm as the places they inhabit, yet, 

 as the water might freeze, they then would be froze over and could not 

 breathe. 



The Surinam Toad [Pipa monstrosa, Laur.]. 

 In a frog with webbed hind-feet, and star-pointed ends of the toes 



i [Hunt. Preps. Phys. Series, Nos. 2857, 3274, 3275, and 3276.] 

 2 [Thecadactylus levis, p. 371.] 



