32 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxx. 



the}^ figured and described their species for the first time, the original 

 definition being merely a comparison with an incorrectly identified 

 Cincinnati species. In the paper mentioned the latter authors figure 

 two specimens which in the collection are labelled as the t^^pes of the 

 species. These specimens agree in one character only, namely, the 

 turbinate growth ascribed to the species by the authors. The zocecia 

 of each, however, are so ditt'erent in size, shape, and arrangement 

 that a lens is not necessary to determine that the two specimens repre- 

 sent very distinct species. The original of fig. Ih^'' is a specimen of 

 Cyjyhotriipa (icermdoHa (Ulrich),-' a species hitherto known onl}" from 

 the Trenton. It is doubtful whether this specimen came from Cin- 

 cinnati, as is stated by James. Still, it is possible that it was found in 

 the Trenton strata exposed opposite Cincinnati along the banks of the 

 Ohio River. The second figured type (fig. 1^/ of the article cited) is a 

 tj'pical example of Monotrypa si(hglol>o.sa (Ulrich),^ found only in the 

 lower part of the Eden shales. Fig. Ic presumably is intended to rep- 

 resent the surface of one of the two types. No matter which one was 

 chosen, the figure is incorrect, since l^oth species have thin -walled, 

 polygonal zo(jecia, with no mesopores in the case of the former and 

 very few angular young cells in the latter. The figure shows rounded 

 or irregular zooecial apertures with subcircular mesopores at their 

 junction angles. 



J. F. James in 1895 states, in his remarks luider the description of 

 Montlealipora selwyni.^ that 21. {Prasopora) selwynil var. hospitalis 

 Nicholson (now Pmsopord hospitalis) is the same as M. turhinata 

 (flames), and that an examination of the internal structure of the two 

 shows their identity beyond a doubt. This author evidently did not 

 base his obsei'vations upon the figured types of M. ( Chaetetes) turhinata^ 

 inasmuch as their internal structure, although difl'erent in each speci- 

 men, is totally distinct from Nicholson's species. Moreover, the last 

 was described b}' the elder James as MonticuJipora wiiiehtllL To add 

 to the confusion, Nickles and the writer verv unwisel}" recorded, as 

 cited above in the synon3miy, Chaetetes turhinatum as a valid species 

 of the genus Jlonotrypa, making Ulrich's Monotrypa suhgtohoxa a 

 synonym. 



To sum up, the first definition of Chaetetes turhinatum is worthless, 

 while the second is based upon two distinct species. These two forms, 

 however, can not be correctly determined from the published figures, 

 since the enlarged view of the surface — the only figure given that 

 might be of any value — is an incorrect representation. Finalh^, a 



"Jour. Ciiu'innati Soc. Nat. Hist., X, 1888, pi. ii. 



b Leptotrypa acerndom Ulrich, Geol. and Nat. Hist. Surv. Minnesota, Final. Rept., 

 Ill, Pt. 1. 189;}, p. 318, pi. xxvii, figs. 24, 25. 



■■ ciiiitiii.s xiihi/lohosa Ulrich, Jour. Cincinnati Soc. Nat. llist., 11, 1879, p. 129, pi. 

 XII, li>rs. 11-11/-. 



