. Bulletin. Science; Natural history; Natural history. Figure I. Helminthoglypta ficldi Pilsbry, penial complex: ec, epiphallic caecum; ep, epiphallus; pe, penis; pr, penial retractor muscle; vd, vas deferens. Transverse sections slightly enlarged from main drawing. raised, roughly rhomboidal surfaces thus defined being more or less produced into papillae. In H. traskii the degree of papulation is variable from race to race; H. t. phlyctaena, for example, the nearest geographic neighbor of H. fieldi in the group, is conspicuously papillose on the spire, the papillae being reduced or absent on
. Bulletin. Science; Natural history; Natural history. Figure I. Helminthoglypta ficldi Pilsbry, penial complex: ec, epiphallic caecum; ep, epiphallus; pe, penis; pr, penial retractor muscle; vd, vas deferens. Transverse sections slightly enlarged from main drawing. raised, roughly rhomboidal surfaces thus defined being more or less produced into papillae. In H. traskii the degree of papulation is variable from race to race; H. t. phlyctaena, for example, the nearest geographic neighbor of H. fieldi in the group, is conspicuously papillose on the spire, the papillae being reduced or absent on the last and penultimate whorls. Helminthoglypta walkeriana bears moderate to strong papulation, frequently eroded from the early whorls but dis- tributed generally over the body whorl and into the umbilicus. Helminthoglypta fieldi tends to develop groups of papillae only immediately be- hind the outer lip of some adult individuals. Scattered papillae, sometimes in linear groups paralleling growth lines, are rare on other parts of the shell, and many specimens have none at all. Occasional papillae occur in the umbilicus. The protoconch of H. fieldi (described from juveniles hatched to captive topotypic specimens, A. G. Smith collection No. 7954) is minutely granular in texture and more or less evidently. Figure 2. Helminthoglypta fieldi Pilsbry, shell. Author's collection #229A; just north of mouth of Santa Ynez River, Santa Barbara County, California. wrinkled radially, particularly on the dorsal sur- face. Protoconch and first neanic whorl are covered with short, evenly spaced, stiff perios- tracal bristles with recurved ends. These are rubbed off all metaneanic and older specimens seen, but a few round, boss-like bristle-bases sometimes remain as far down as the third or fourth whorl. Other authors have sometimes termed these bosses "papillae," but they are periostracal in origin and not homologous to the papillose sculpture previously described for the adult shell
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