344 A. E. Verrill—The Bermuda Islands; Coral Reefs. 
Spirastrella mollis, sp. nov. Plate xxxvp, fig. 5. 
An encrusting species forming soft films .5 to 3™™ or more thick 
on dead, cavernous corals, and also penetrating into the cavernous 
spaces,—perhaps a boring sponge when young. Surface smooth ; 
no oscules nor pores visible to the naked eye in alcoholic specimens ; 
interior without visible canals. Skeletal spicules, long slender tylos- 
tyles, scattered and in groups (fig. 5, a), mostly with regular well- 
rounded heads, but some have ovate or elongate heads ; in some the 
heads are much reduced. Microscleres (0,4') are relatively large, 
spined spirasters, abundant in the cortical layer ; they mostly have 
three or four whorls of sharp conical spinules ; some are strongly 
curved (b’), 
(To be continued.) 
SOURCES OF ILLUSTRATIONS IN THE TEXT. 
The following cuts are from photographs and drawings by Mr. A. Hyatt 
Verrill :—1, 20, 30, 54a, 346, 360, 36c, 37, 38, 39, 40, 41, 43, 430, 45, 59, 59a, b, ¢, 
60, 61, 62, 63, 66, 67, 70, T1a, b, 72, 72a, b, 73, 75, 77, 79, 80, 81, 82, 83, 84, 85, 
90, 91, 94, 95, 96, 96a, 97a, 99, 100, 101, 101a, 102, 103-114, 116a-119, 121, 122, 
125-128, 129, 129a, 131-135, 157, 138, 141, 144-162, 164, 176-180. 
The following were by Mr. M. C. Cooke :—6, 16, 18. 
The following are from photographs bought in Bermuda:—8, 9, 10, 14, 15, 17, 
21, 22, 25, 33a, 33b. 
The following were loaned by the publishers of Webster’s International 
Dictionary :—386, 36a, 43a, 142. 
The sources of others are given under the cuts. 
