72 PROCHHDINGS OF THE MALACOLOGICAL SOCIETY. 



considered allies of the Capulidae. The horseshoe-shaped form of sear 

 is a secondary character and not a criterion of affinity, as paired scars 

 would be. 



Pilsbry remarks of Platyceras that " the fusion of this genus with 

 Capulus . . . is hardly justifiable" (6i, p. 461). 



Under these circumstances I would advocate the removal of these 

 early forms from the Capulidte and their r,elegation to the Prostrepto- 

 neiira, the primitive stock whence both the Docoglossa and the 

 Khipidogiossa were derived. 



Still more difficult is the case of SuhuUtes. Fo palaeontologist seems 

 quite to know what to do with this genus. Zittel {59 and 60) puts 

 them with a somewhat miscellaneous assemblage in the Pja-amidellidse 

 and next before the Melaniidse in his Ctenobranchia. Lindstrom 

 {28, p. 192) created the family Subulitidae for SuhuUtes and 

 Eucliry&alis, to which also he considered Btdimorpha and Fusispira 

 probably belonged. Fischer {llj., p. 770) forms them into a family 

 (with Fusispira and Euchrysalis) near the end of the Tseniogiossa, but 

 adds that they ought to be placed after the Strombidae, which with 

 him come early in the same section. Tryon (51, p. 246) includes 

 them in Kuliinidae. Pilsbry (in Zittel, 61, p. 457) retains them in 

 Pyramidellidae, putting that family as Fischer does in the Gyranogiossa, 

 but at the same time admits that they "probably form a separate 

 family." Ulrich {52, p. 1069) keeps them in a separate family; he 

 retains Siihdites for the long, slender, terebelliform species, and wisely 

 creates a new genus, Cyrtospira (p. 1073), for the short, curved forms; 

 he further associates with these Fusispira (p. 1075) for the more 

 tumid forms. Finally, Pelseneer {Ifl, p. 154) makes the Subulitidae 

 the 25th of his 55 families of Taeuiogiossa (in which the Gymnoglossa 

 are included), placing them between the Melaniidae and Nerineidae, 

 the Pyramidellidae being his 53rd family. 



Lindstrom's summing up of this question of the Subulitidae is 

 probably the one that will most appeal to all. He says {28, pp. 192, 

 193) : " What characterizes them all, besides the elongate and smooth 

 shells and the narrow aperture with incomplete peristome, is the 

 important feature of a distinct apertural canal, situated exactly as 

 in all Siphonostomata and quite as much developed as in several 

 of them . . . We see consequently in this family the most ancient 

 representatives of the great section of the siphonostomous shells. 

 The systematic place of the species of this family is by far not as 

 easily cleared up as their nature of siphonostomous shells, and I think 

 that this question must for the present be left undecided." 



Nevertheless, the consensus of opinion appears to be that the 

 Subulitidae belong to a higher order of Gastropoda than the Aspido- 

 branchs, in which case it would seem that three out of the four 

 principal divisions of the Streptoneura are first met with almost 

 simultaneously in the oldest known fossiliferous rocks. 



The fifth division, the Stenoglossa, comprising the more highly 

 differentiated genera from Turhinella to Conus, made its appearance 

 geologically much later, a form ascribed to Fusus being the first to be 

 met with, in beds of Cretaceo.us age. The Jurassic Purpuroidea, 



