GENERA RnYNCIIONELLA AND LEIORHYNCnUS. 271 



Since the preceding matter was in print, as cited above (Vol. 4, Pal. 

 N. Y., pp. 332-4), my attention has been called to an article published in 

 the Smithsonian Contributions to knowledge, 172, and entitled " Palaion- 

 tology of the Upper Missouri," etc., etc., Part I, by F. B. Meek and F. 

 V. Hayden ; on the 16th page of which I find the following note : 



''In the Fifteenth Report of the Regents of the University of N. Y.,* 1852, pp. 

 " 154-5, Prof. Hall proposes the name Zygospira for a genus of which Producta 

 '' modesta, Say. is the type. It seems, however, that Mr. Comrad had suggested for 

 ** this shell the generic name Stenocisma, which Prof. Hall proposes in the first vol. 

 *' Pal. N. Y. (1847, p. 142) to adopt, should this type prove to belong to a distinct 

 "genus. As there was no necessity for a new name, Stenocisma will have to take 

 " precedence over Zygospira.^- 



The tone of this paragraph denotes the language of a man accustomed 

 to speak with authority, and no one is expected to take exceptions. " It 

 ^^ seems ^ however^ that Mi'. Conrad had suggested for this shell the generic 

 ^^name Stenocisma," etc. Where did Mr. F. B. Meek get the informa- 

 tion that Mr. Conrad had ever suggested for Producta iJiode^t a (SAY,sp.) 

 the name Stenocisma, or any other name ? The conceit and ignorance 

 shown in this paragraph are only equalled by its disingenuousness. I have 

 already quoted the remarks of Mr. Conrad in reference to the Grenus 

 Stenocisma .,\ from his Second Annual report. 



In the First Volume of the Palaeontology of New-York, all the Brachio- 

 poda of the general form of Atrypa, Rhynchonella, Terehratula, etc., were 

 described under the generic name Atrypa, since they had not then been 

 sufficiently studied to assign them to their proper relations ; and the use of 

 the term Atrypa had, in a measure, superseded that of Terehratula. After 

 describing Atrypa extans, A. nucleus, A. cuspidata, A. his?ilcata, A. defecta, 

 A. recurvirostra, A. cxigua and A. modesta, I wrote as follows at the close of 

 the last description. "This species, with the three preceding ones, form a 

 "group, presenting characters which may require their separation from the 

 '* true Atrypa. These characters consist in the elevation of the dorsal $ 



(Rhynchonella formos a) vfhioh. was referred by Mr. Coxrad to *' the common Silurian 

 bivalve T. schlotheimii." I have in my possession a lithographed plate of the fossils of 

 'the Lower Helderberg group by Mr. Conrad, with the names, in his own hand, written 

 beneath the figures; the species I have since designated as R. formosa having there been 

 identified with Terehratula schlotheimii. 



' Although the generic characters were not fully described, and with imperfect reference 

 to species, I think it preferable to adopt this name instead of introducing a new one. 



'The name Hemithyris, applied by some authors to certain rhynchonelloid forms, has 

 been used to include very heterogeneous materials; and without citing a long list to prove 

 this, I may mention H. angustifrons, M'Coy, H. sulntndata, M'Coy, H. hemisphericay 

 var. scotica. M'Coy ; all figured on the same plate, and belonging to three distinct genera ; 

 the first named being undoubtedly a Meristella, and having internal spires. This 

 generic term, therefore, cannot be adopted unless redefined and very much restricted in 

 its application.' 



* The Fifteenth Annual Report of the Regents of the University of the State of New- 

 York, on the Condition of the State Cabinet of Natural History, etc., was published in 

 1862. The Fifteenth Annual Report of the Regents of the University of the State of 

 New-York, was published in 1787. The two documents should not be confounded. 



f Pal. N. Y., Vol. 4, p. 144 and page 269 of this Report. Had the species referred to been 

 the T. schlotheimii, we should have had the name Stenocisma proposed for the type of 

 the Genus Camarophoria. 



X The terms ventral and dorsal were then used in reverse sense of that in which they 

 are now employed. 



