110 BULLETIN OF TIIK 



Glyphostoma gratula Ball* 



Plate XII. Fig. 10. 



Pleurotoma (Drillin) gratula Dall, Bull. M. C. Z., IX. p. 64, August, 1881. 

 Pleurotoma {Drillia) incilis Watson, Linn. Soc. Journ., XV. p. 425, October, 1881. 

 Eeport Chall. Gastr., p. 304, pi. xxiv. fig. 5, 1885. 



Shell similar to the last, but white, with the spiral sculpture sharp instead 

 of rounded and the intervals wider and more irregular; the shell is more 

 slender in proportion to its length, and the last whorl smaller in proportion 

 to the spire ; the ribs (about 16) are sharp and the spirals minutely nodu- 

 lous where they cross the crests of the ribs ; the latter cross over the periph- 

 ery and grow gradually smaller to the canal, never bifurcating; the varix 

 is much thinner, and the indentation behind it much less marked ; there 

 is no gathering up of nodulations at the suture, and the anal fasciole is 

 smoother or even quite free from spiral threads. The largest specimen had 

 not completed its lirations in the aperture and on the inner lip, but they 

 seemed fewer, coarser, and more irregular than in G. Gahhii. Max. Ion. of 

 shell, 17.5 ; of last whorl, 10.5 ; max. lat. of shell, 6.0 mm. There are seven 

 normal and three nuclear whorls. 



Habitat. Gulf of Mexico, at Station 2398, in 227 fms., mud, between the 

 Mississippi delta and Cedar Keys, Florida; and Station 2150 ir^ 382 fms., ooze, 

 near Old Providence, U. S. Fish Commission. Off Culebra Island, in 390 fms., 

 Challenger Expedition. Station 43, Gulf of Mexico, in 339 fms. ; Station 19, 

 in 310 fms. Off Havana, in 292-805 fms., Blake Expedition. Bed of the Gulf 

 Stream, Pourtales, in 447 fms. 



Both the specimen figured by Mr. "Watson and that here figured are not 

 quite mature, and do not show the adult mouth characters. Indeed, it was 

 not until I had examined the Fish Commission specimens that I realized the 

 true position of the species. The species varies considerably as regards the 

 height of the spire in proportion to the last whorl. Perhaps Mr. Watson's 

 name may be retained for the shorter ones as variety incile. 



Glyphostoma phalera n. s. 



Shell white, acute, seven-whorled ; nucleus glassy, rounded, not keeled, hav- 

 ing about 1| whorls ; remainder of the shell solid, finely granulated with micro- 

 scopic granules, which are arranged in close, even transverse lines between the 

 spirals; spiral sculpture of numerous rather coarse flatfish threads with about 



* This is one of a few species of Pleurotoma in which, publishing almost simul- 

 taneously, my friend Mr. Watson and myself have unintentionally both named 

 the same species. Our manuscripts went to the printer about the same time ; but 

 mine were published immediately, while his were several months delayed. I had 

 thought of resigning my names in favor of his, as first figured, but have been ad- 

 vised by several naturalists that this was not admissible, and would cause confusion 

 in the nomenclature. 



