1916. J. HORNELL : Indian Varieties and Races of Turbinella. I15 
9 
seen normally in var. obtusa, but are made up.usually of parallel rows of distinct 
nodular elevations, miniatures of the coarse knobbed nodes of the shoulder row. In 
many large shells they gradually decrease on the body whorl as they approach the 
lip. When the periostracum is removed the position of the periostracal nodes in the 
shoulder rows is indicated by very slight eminences or swellings, which are the 
vestigial remains of strong shoulder knobs such as are seen in the related genera 
Fulgur and Cynodonta. Beneath each of the body rows a continuous obscure narrow 
band-like ridge, very feebly developed, can usually be traced; only in large indivi- 
duals with coarse and thick periostracum are there indications of minute vestigial 
knobs at intervals upon these ridges; in young specimens slight furrows often take 
the place of these raised lines (Pl. X, fig. I). 
Fic. 2A.—Elongated example of Turbinella pirum acuta (Tuticorin race). 
Fic. 2B.—Squat example of T. pirum acuta, from same region. 
Drawn from selected shells to show the extremes in form seen in this race. 
In medium-sized shells, say under 6 inches in length, the ratio of axial length to 
the diameter of the body whorl ranges within narrow limits from 1°75 to 1°85. 
Hence the shell as compared with the two forms of obtusa is relatively narrow. Ina 
few old shells of 7} in. in length the body whorl is considerably inflated, altering 
slightly the ratio of width to length, but in ordinary large individuals the more 
slender form is retained unaltered. 
The colour of these shells is usually a pure porcellaneous white, more or less 
suffused with pale pink interiorly at the oral aperture Small shells sometimes show 
reddish spots, very variable in number and distribution. 
The apex never shows wearing down due to abrasion such as is common in the 
Tirupalagudi race of T. pirum obtusa (typica) and in var. comorinensis about to be 
