100 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 78 



LEPIDILLA ANOMALA Matthew 



Plate 7, Figures 20-23; Plate 5, Figure 17 



Lepidilla anomala Matthew, Trans. Ro.val Soc. Canada, vol. 3, sec. 4, 1886, 

 p. 62, pi. 6, figs. 18a-c; vol. 8, 1891, p. 130, pi. 11, fig. 2. 



We have refigured the type and only specimen of this species, which 

 is in such a state of preservation that the real affinities can not be 

 determined without a study of additional material. Matthew has 

 brought out the essential features in his generic description, which is 

 copied above. 



Occurrence. — Middle Cambrian (Acadian, Clc2): Hanford Brook, 

 New Brunswick. 



"LEPERDITIA" VENTRICOSA Matthew 



Plate 7, Figure 35 



Leperditia ventricosa Matthew, Trans. Royal Soc. Canada, vol, 7, sec. 4, 1890, p. 



159, pi. 7, figs. 12 a-d; Trans. New York Acad. Sci., vol. 14, 1895, p. 137, 



pi. 8, figs. 5a-5d. 

 Isochilina ventricosa Matthew, Canadian Rec. Sci., vol. 8, 1902, p. 453. 



This species is represented in the Matthew collection of types by 

 two imperfect specimens, one a valve, the other the impression of same 

 or another valve in the hard sandstone matrix. One margin is fairly 

 well preserved and shows a broad, thick flange. The remaining por- 

 tions of the outline are not in condition to prove that this flange extends 

 around the whole of the free margins, but judging from the general 

 preservation of the specimens, it is thought likely that if it had, more 

 of the flange would have been retained. As preserved the shape is 

 irregularly subovate, the hinge nearly straight, the dorsal angles not 

 very conspicuous. The surface is strongly convex and entirely 

 covered with a network, the meshes of which increase greatly in size 

 toward the middle of the valve, where they are easily visible to the 

 naked eye. The shell is thin, and its composition apparently the same 

 as in Bradoria and allied genera. The length is about 8.0 mm., the 

 height about 6.5 mm. 



There is nothing about this valve suggesting even remote alliance 

 to Leperditia, or to Isochilina, as supposed by Matthew. The com- 

 position of the valve is as in the Bradoriidae, and hence quite different 

 from the much more calcareous shells of Ostracoda. Obscure tuber- 

 cles are noted near one of the angles, but they are too indefinite to be 

 compared with those in Bradoria. Still, this feature might be waived 

 and the species referred to that genus were it not for the thick anterior 

 (?) flange. Under the circumstances it is thought probable that L. 

 ventricosa will finally be referred to an as yet undescribed genus. 



The character of the surface ornamentation, especially the fact 

 that the pits, or the meshes of the network, increase in size inward 

 from the margins, seems to be exactly the same as in the even more 



