On Streptclasma Profundurn. — Sardesou. 271) 
rich's species. More recently Whiteaves has described S. 
rohustum (1897). 
Zajihrentis canadensis Billings (1862), Z. «^";/^v Bill, and 
Z. helUstriata Bill. (1865) are especially noteworthy species 
since Eastman in his translation of Zittel substitutes the 
name Z. canadensis Bill, for S. corniculitm Hall, without how- 
ever reducing the genus Strejife/asnia to a synonym for Zapli- 
rentis which, if his identification is true as it evidently is, 
must follow\ Rominger has already shown that the two gen- 
era are not clearly separable.* James Hall retains it as a 
subgenus of Zaphre)itis.\ 
From investigation it appears that some of the most im- 
portant characters as well as unimportant ones that may be 
seen in ^S". profandum, have been misunderstood or overlooked 
and an account of my own observations is therefore presented 
here in order to re-affirm the facts or add others to the know- 
ledge of these corals. 
STREPTELASMA PROFUNDUM Owen sp. 
CyatJiophyUuiii profunduni Owen (1811) GeologieaJ Exploration of 
Iowa, Wisconsin and Illinois, pi. 16, f. 5. 
"Lower lead-bearing beds" i. e. Beloit formation, or Black River. 
Streptelasma expansa Hall (1847) Pal. New York, vol. 1, p. 17, pi. 4, 
f. 6a-b. Chazy formation. 
Streptelasma profunda Hall (1847) Pal. New York, vol. 1, p. 49, pi.. 
12. f. 4a-d. 
Streptelasma cornicula Hall (1847) Pal. New York. vol. 1, p. 60, pi. 
25, f. la-c. Trenton limestone. 
Streptelasma crassa Hall (1847) Pal. New York, vol. 1, p. 70, pi. 25 
f . 2a-c. 
Streptelasma midtilamellosa Hall (1847) Pal. New York, vol. 1, p. 70 
pi. 2.5,f. 3a-c. 
Streptelasma parvula Hall (1847) Pal. New York, vol. 1, p. 71, pi. 25, 
f. 4a-c. Trenton limestone. 
Streptclastna corniealam Edwards and Haime (1851) Polypicrs fossiles 
p. 398, pi. 7, f. 4. 
Streptelasma cornicula Billings (1857) Caoadian Nat. and Geol.. vol. 
1, p. 122, f. 3-4. Trenton limestone. 
Streptelasma profunda Billings (1857) Canadian Nat. am,] Geol. vol. 
1, p. 123, f. 7, 8. Black River to Trenton formation. 
Petraia rustica Billings (1858) Rep. Progress Geol. Sur. Canada for 
1857, p. 168. Hudson River group. 
*Foss. Corals, p. 140. 
tPal. N. York, vol. 6, p. xi. 
