1921] NATURAL SCIENCES OF PHILADELPHIA. 381 



In 1873, Gabb described Dolophanes melanoides as a new genus 

 and species, with the following note on its systematic position: 



"The first impression produced on looking at this little shell is 

 that it is probably a Melania; but apart from all of its three hundred 

 associates being marine, which would render such a reference im- 

 probable, it has a grouping of characters which ally it so closely to 

 StndhiolarLa, that lam convinced that it is most probably a near 

 related genus. Its spire is very like that of many species of Strombidae, 

 and in the details of its mouth it differs from Siruthiolaria in having 

 a thinly encrusted inner lip, an acute outer lip and an obsolete um- 

 bicilus, instead of the thickened margins and no umbilicus of that 

 genus. I have tried to identify this species with the shell de- 

 scribed by Guppy as Melanopsis capula which it seems to resemble 

 somewhat in form and size. But that author gives his shell but 

 seven whorls, and does not describe or figure the flattened tops of 

 the volutions, which are a marked character of the present species. 

 There are also other differences which, however, might be explained 

 by want of care in the artist, but which nevertheless, lead me to 

 believe that, while there may be a generic relation between the two 

 shells, they are most probably different species." 



In 1881 Dr. W. H. Dall followed the description of Pleurotoma 



{Mangilia) colurnbella with the following remarks: 



"This is a species, which in the absence of the soft parts, is dif- 

 ficult to locate. It is possible it should be referred to Bela. It is 

 not unlike one or two Arctic species." 



In the "Blake" Report, 1889, Dr. Dall refers P. colurnbella, with 

 doubt, to Dolophanes melanoides as a variety; also placing Melanop- 

 sis capula in the synonymy, with a query. He further notes : 



"Two specimens of this form are in the collection. Guppy 's 

 specimen, from the figure, was evidently deformed. These differ 

 from it, due allowances being made for deformity, in being narrower 

 and in the narrow shoulder in front of the suture. 



"The specimen originally serving as type of M. colurnbella is the 

 roundest and the groove behind thesiphonal fasciole is reduced to a 

 mere chink. In the Havana specimen the chink is considerably 

 larger and the shoulder more prominent. It seems to stand about 

 one-third of the way from D. colurnbella to D. gahbi. I cannot be 

 sure, with so little material, but I suspect this gap might be filled 

 up by a graduated series of specimens if we had material enough. 

 Still, as the forms are not yet connected, and have already been 

 named, it seems best to leave them separate for the present. " 



Dr. Dall further writes, under the description of Dolophanes 



{melanoides var.?) gabhi, ("Blake" Report, p. 270): 



"This genus was referred to the Struthiolariidae by its author, a 

 reference which has been questioned by all those who have had 



