126 PROCEEDINGS OP THE ACADEMY OF 



of respiration; but it is difficult to understand how the fish had 

 procured its food. The cyprinoids, generally, are remarkable for 

 their small toothless mouth, but it is, nevertheless, important in 

 its prehensile capacity. The condition of the specimen is, of 

 course, a deformity, but appears to be the result of a want of 

 development of the jaws, and not of accidental violence. Dr. 

 Lawrence observes that a few of such fishes are caught every 

 year in the Ouachita, sometimes with the oral orifice so small as 

 barely to admit a crow-quill, and occasionally without even the 

 vestige of an orifice. If the last condition really occurs, the fish 

 can only supply itself with food and with water for respiration 

 through the branchial fissures, by the alternating outward and 

 inward movements of the opercula. 



On Ouramceba. Prof. Leidy remarked that his description of 

 the curious rhizopod, he had named Ouramoeba, in the Proceed- 

 ings of Ma}" 12, 1874, having been noticed by Mr. Archer, of Dub- 

 lin, this gentleman had directed his attention to notices of the same 

 animal described in the Proceedings of the Dublin Microscopical 

 Club for Feb. 186fi and Oct. 1873. In these notices Mr. Archer 

 regards the animal only as an Amoeba villosa in another condition 

 from that ordinarily observed. Mr. Archer's description clearly 

 refers to the same animal as that named Ouramceba, in which he 

 aptly compares the bunch of tail-like appendages to "a bundle of 

 dipt-candlcs," and it is of some interest to know that the singular 

 creature, like so many other rhizopods, is common to Europe and 

 America. 



While Mr. Archer regards the "Amoeba with remarkable poste- 

 rior linear processes" (Proc. Dublin Micr. Club, Oct. 1873,314) as 

 exhibiting another condition of existence of an Amoeba from the 

 one usually observed in the genus, he gives no evidence that such is 

 the fact. Until this is proved to be the case the peculiar charac- 

 ter of the animal justifies its separation as representing a distinct 

 genus with the name of Ouramoeba. 



Since the latter was first noticed, many additional specimens 

 have been observed, and though, as in the case of rhizopods gene- 

 rally, they exhibit considerable variation, it appears that several 

 species may be distinguished. 



The genus may be thus characterized : 



Ouramceba. Body, as in Amoeba, consisting of an everchang- 

 ing fluctuating mass of jelly, composed of a granular entosarc, 

 including a contractile vesicle and a discoid nucleus, and defined 

 by a clearer ectosarc. Pseudopods usually digitiform, projecting 

 anywhere but usually in a direction differentiated as forward, and 

 composed of extensions of the ectosarc closely accompanied by 

 included extensions of the entosarc. Posterior part of the bod3" 

 furnished with one or more tufts of non-retractile, rigid, linear 



