and allied Brachiopod genera. 399 
In September, 1862, Prof. A. Winchell, in his “ Descriptions 
of fossils from the Marshall and Huron Groups, of Michigan,” pub- 
lished a description of Centronella Julia, in which he describes the 
loop, which is proved not to bein accordance with that of Cen- 
tronella as described and illustrated in the Canadian Naturalist 
and Geologist, vol. iv, April, 1859. 
Through the kindness of Prof. Winchell, I have been put in 
possession of some specimens of this species, with parts of others 
illustrating the internal structure, together with drawings repre- 
senting the loop. 
n examination of the external characters shows that the shell 
has the form and texture of Crypionella. ‘Both valves with reg- 
ular lens-like convexity, shell obsoletely striate concentrically, 
and having a minutely punctate structure.” The form and other 
characters of the cast are like those of species referred by me to 
Cryptonella. In the ventral valve are two delicate, slightly cur- 
ving dental lamellze, which are shown in casts by a narrow slit 
on each side of the beak. “The casts exhibit on the ventral 
side a delicate impressed line extending from the beak to the 
middle, and on the right and left of this a fainter one; on the 
dorsal side, a median impression, with two fainter ones on the 
night and two on the left.” These characters appertain to the 
casts of Cryptonelia (see fig. 9), as shown in the ventral side of 
large individuals; having three defined, slightly impressed spa- 
ces, limited by narrow lines which extend to the middle of the 
ang below which there are sometimes vascular impressions 
Visi 
ings of Prof. Winchell, is shown in figures 1 and 2, which are 
four times enlarged, and are thus described: “A delicate ribbon- 
like loop originates from the stout blunt crura on each side of 
€ socket-valve, having its flat sides at first vertical; the two 
branches of the loop proceed at first in lines parallel or a little 
Convergent, and then gradually diverge, widening as they pro- 
and assuming an inclined position, until, approaching the 
front of the valve by a regular curvature, the lower edge has 
become anterior, giving the band an angle of 30° with the plane 
temporary wall formed by disease of the animal, because both spires are crowded 
into the smaller of the two cavities, the L being empty.” 
ne genus Charionella, therefore, clearly belongs to the Spiriferide, and the 
typical species cited are, in nose originally placed by me under the genus Mfe- 
‘Tstella, in 1860 (Thirteenth Report on the State Cabinet, p. 84), and han oa under 
Terebratula, from the characters of which I proposed the genus Cryptonella in 1861. 
‘The former belong to the Spiriferide, and the latter to the Terebratulida. 
