THE NAUTILUS. 131 



ON A NEW FLORIDIAN CALLIOSTOMA. 



BY WILLIAM HEALET DALL. 



In March, 1903, the U. S. Fish Commission steamer Fish Hawk 

 obtained some casts of the dredge in the straits of Florida. This 

 material has recently been turned over to the National Museum, and 

 proves to contain several items of interest. At Station 7511, in 45 

 fathoms, off Fowey Rocks, was dredged a species of Calliostoma 

 which appears to be new ; at Station 7516 fragments of Oniscidia 

 dennisoni were obtained, with a specimen of Scala (Acrilla) retifera 

 Dall, 28 mm. in length, and at Station 7511 a fine specimen of the 

 rare Subula floridana Dall, described originally from the Blake dredg- 

 ings. As it has been shown that the name Eutrochus Adams is pre- 

 occupied, J replace it by Leiotrochus Conrad, 1863, typified by L. 

 distans Conrad, of which the type has turned up in the National 

 Museum (see Trans. Wagner Inst., iii, pp. 399 and 402), and proves 

 to be a mature specimen of the shell named Trochus conus by H. C. 

 Lea in 1845. Astele Swainson, 1855, seems to be more closely re- 

 lated to Solariella, and is described as " with no columella," the inner 

 lip being simple and arcuate. Conrad's diagnosis is incorrect, as the 

 reader will see by referring to the above-mentioned data. His type 

 is smooth, with, in the adult, a narrow, deep umbilicus and a distinct 

 Calliostomoid pillar. Owing to Conrad's contradictory diagnosis of 

 1863, I hesitated, in 1892, to accept his name, but as things now 

 stand it seems necessary to do it or to propose a new one. The 

 description of the species is as follows: 



Calliostoma (Leiotrochus) marionas ri. sp. 



Shell acutely conic, with the sides of the spire slightly concave, 

 ten-whorled, brilliantly polished, color a rich brick-red, mottled near 

 the periphery with whitish fiammules; nucleus translucent white, 

 tilted obliquely ; sculpture, on the subsequent four or five whorls, of 

 five (5) granular, spiral ridges, separated only by narrow incised 

 lines, with a more conspicuous ridge just above the suture ; subse- 

 quently the ridges become flattened, wider and more or less spirally 

 striate on their tops, while the original five incised lines retain a 

 darker color than the rest of the surface ; the suture is not strongly 

 marked, and runs just below the periphery of the preceding whorl ; 

 base slightly convex, with ten or eleven similar incised spiral lines 



