MUSF.UM OF COMPARATIVE ZOOLOGY. 145 



above the margin of the loot, iiu'etiiig over a roninl camlal mucus-pore : dis- 

 tinct locomotive dislc to It nit: external orifice of cimibiia'd generative organs 

 on ri'dit side of body, far belund the eye-peduncles : of respiratory and ex- 

 cretory organs on the right of the mantle under the peristome : jaw smooth, 

 with median projection : lingual membrane as in Zonitcs, central teeth tricus- 

 pid, lateral teeth bicuspid, marginals aculeate. 



Shell external, Vitrina-like. 



The above generic name is proposed for the shell described as Vitrina latissivia 

 (p. 136), as it combines the characters of Vitrina and Zonitcs. The animal dilfers 

 from Vitrina by having simple, not bitid, marginal teeth to the lingual mem- 

 brane, and by a caudal mucus-[ujre, with longitudinal furrows alx)ve the margin 

 of the foot, and by the want of an appendiculate mantle. From Zonitcs it 

 diflers only in the ibrm of the shell, though the caudal mucus-pore seems to be 

 circular, with projecting process when open, rather than a simple longitudinal 

 slit, as in Zonites supprcssus. There appears no developed appendiculate mantle 

 process. 



The genus in my arrangement will I'oUow Zonitcs. 



Vitrinizonites latissinius, Lewis, (p. KG.) 



Plate I. Fig. H. Plate III. Fig. A, B. 



I hi/re add a figure of the animal in mulinn (r\. III. l"ig. A), not fully 

 extended, drawn by Miss Ennna I'ringle. The caudal mucus-pore is circular, 

 bordered with a nai'row transversely grooved rim ; and when closed is covered 

 completely. When open the cover is raised along its longitudinid centre into 

 a sharp carina, leaving posterioidy, Avhen seen from l)ehind, an erect triangular 

 opening. It thus differs from the simple hiMgitudinal slit ibuud in most of the 

 American species of Zonites, such as frinhi:is, capnodcs, fuliginosus, inornatus, 

 demissus, ligerus, suppressus, the last figured in Vol. V., Fig. 47. Z. Umngatus, 

 however, has a nearer approach to the circular pore of Vitrinizonites. 



The genitalia are figured ou Plate III. Fig. B, The ovary is very large (or.) 

 and stout : the genital bladder (;/. //.) is glol)ular on a short, narnnv duct: the 

 penis-sac (p. s.) is very long, narrow, cylindrical, receiving the retractor 

 muscle (/•.) near its basal termination, and merging at its ai)ex into the vas 

 deferens (v. <?.). The penis-sac has not the accessory process found in Zonites 

 capnodcs, friabilis, Icevigatns, inornatiis, fulic/inosus, and Htujili. 



The species has been found from Carter Co. to Blount Co., Tennessee, on 

 the dividing line between Tennessee and North Carolina. 



On Roan ]\Iountaiii it is usually found under damp moss. 



I am indelited to Miss Annie E. Law for the opportunity of exann'ning tlie 

 specimen figured. She collected it in June, 1879, at the original locality, Bald 

 ^Mountain, Blount Co., Tennessee, on dividing line with North Carolina. At 

 Washington Co., Tennessee, it was Ibuud by Dr. Bugel. Airs. G. Andrews 

 fouml it on Roan Aloiiiitain, in Nortli Carnlina (over (;,()<)n feet), on the divid- 

 voi, XI — NO 8. 10 



