“ 
THE NATURAL HISTORY SURVEY. 395 
time before his death, were pronounced by him to be vermon- 
tanum. It is one of the commonest Spheria found in the area, 
ranking next to fadalein this respect. It is easily distinguished - 
from the related species by its triagonal form and less dis- 
tinctly marked umbones. 
p.113 et al. Allreferences to solsdulum should be changed 
to vermontanum. 
p. 114. 
38. Sphzrium stamineum Conrad. 
This species is very common in Lilycash Creek, near Joliet, 
Ill., where it has been collected by Mr. J. H. Handwerk. The 
specimens from this locality are very variable, some being typ- 
ical in form, yellowish in color and with the ends of the shell 
broadly rounded, while others are very dark horn color, the 
ends more rounded, and the ventral part more regularly in- 
flated; the umbones are more coarsely sulcated. Some speci- 
mens from this locality have a wholly inversed hinge. S. stvza- 
tinum and S. simile have also been found in large numbers in 
Lilycash Creek. 
p. 117. After S. seme add the following: 
151. Sphzrium lilycashense Baker. Text figure 137. 
Spherium lilycashense BAKER, The Nautilus, Vol. XII, No. 6, p. 65, 
Oct., 1898. 
Shell: Of good size, inflated, rather solid, although not 
so solid as either staminium, striatinum or simile, subequilateral, 
indistinctly quadrangular; umbones slightly elevated, well 
rounded, a little anterior of the center of the shell, marked 
by numerous rather heavy ridges, the beaks closely approxi- 
mate; dorsal and ventral margins slightly curved; anterior end 
rounded, posterior end very broadly rounded; umbonal slopes 
very much rounded; surface shining, growth lines numerous, 
coarse, closely set; color varying from light yellowish horn to 
rather dark horn, with an occasional zone of yellowish; liga- 
ment weak, light brownish in color; cardinal.teeth small, simi- 
_ lar in shape and position to those of striatinum, lateral teeth 
quite solid, double in the right and single in the left valve, 
short, lamellar, nearly straight, the single left valve teeth much 
more elevated than the double right valve teeth; muscle scars 
and pallial line faintly visible; nacre bluish, the portion near 
the umbones transparent; cavity of the beaks rather deep. 
Length, 14.00; height, 11.00; breadth, 8.50 mill. 
h 1S.00 es f 10.00; i 8.00 “ 
af 12,50; °°“ 9.75; ss ps 
