THE NAUTILUS. 103 



of the Chesapeake fauna as developed in Virginia and Maryland, 

 only a few species are held in common, while with the Upper or 

 Duplin Miocene horizon of N. C., agreement is much closer, due as 

 much to similarity of climatic conditions as to a similarity in age. 



Besides Oardium gahestonense Harris, two other species are avail- 

 able for correlation in both the Chesapeake beds of Maryland and 

 the Miocene of the Galveston well, namely Mytilus conradinus Orb. 

 and Grassinella galvestonensis Harris. These two species are rather 

 abundant and occur in nearly the whole series of our Miocene beds. 

 The former from New Jersey southward, the latter as far north as 

 Maryland. Cardium galvestonense however until its present dis- 

 covery in the Choptank formation of Maryland has escaped notice 

 outside of its type area. Its distribution is such as to indicate, that 

 it may be expected anywhere in the intermediate area. Its rarity 

 outside of the Texan region, where it is abundant, indicates that it 

 is a warm-water-loving form, finding as Professor Harris notes, its 

 nearest relations with Antillean species. So far it is the only 

 Trigoniocardia discovered in our Atlantic coast Miocene beds, 

 although the group is abundantly represented in the Oligocene 

 beneath. 



NOTE ON CLEMENTIA OBLIftUA JUKES-BROWNE. 



BY AVM. H. CALL. 



Mr. A. L. Jukes-Browne in the Annals and Magazine of Natural 

 History for July, 1913, p. 60, has published a description of a new 

 species of dementia under the specific name of obliqua, which was 

 supposed to come from Porto Rico. By the kindness of J. Cosmo 

 Melvill, Esq., I have been able to examine one of the two specimens 

 upon which this species was founded. It proves not to be a Clem- 

 entia, not to come from Porto Rico, and to be a species described by 

 Carpenter under the name of dementia subdiaphana forty-eight 

 years ago. As dementia was, according to Adams and Woodward, 

 a Dosinoid animal, and the soft parts of this species are Veneroid, it 

 was transferred by me to the genus Marcia, section Venerella, in my 

 revision of the Veneridae in 1902. I figured the species in the Pro- 

 ceedings of the U. S. National Museum in 1891 from an exception- 

 ally rotund specimen. Mr. Jukes-Browne's figures are of the more 



