206 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [500} 
RADIATES. 
Echinoderms. 
Page. Page. 
Strongylocentrotus Drébachi- A. arenicola ......----.----- 326 
OUSIS, sake R dicaaeteea ete s 496 | Cribrella sanguinolenta...... 496 
Asterias vulgaris......-..--- 496 | Ophiopholis aculeata ......-. 496 
Acalephs. 
Page Page 
Clytia Jobnstoni-....-......- 408 | Sertularia argentea ......... 408. 
C. intermedia.........--..-- 408 | S. cupressina ........-....-. 408 
Orthopyxis caliculata........ 408 | Hydralimania faleata......-. 408 
Platypyxis cylindrica........ 408 | Plumularia, species ......-.. 407 
Campanularia volubilis...... 408 | Antennularia antennina ..... 497 
C. flexuosa .... ...----.---- 327 | Eudendrium ramosum.....-. 408 
Obelia geniculata ......-.... 496 | E. dispar -....---.-----++--- 408 
O. dichotoma ..-...----.---- 407 | Pennaria tiarella......... .- 327 
O. flabellata .........-...--- 497 | Thamnocnidia tenella........ 407 
QO. dlaphana, ... san cend eee 327 | Hydractinia polyclina .....- 328 
Polyps. 
Page. Page. 
Aleyonium carneum......... 497 | Edwardsia lineata......-.--. 497 
Metridium marginatum...... 329 | Astrangia Dane .-........-- 408 
PROTOZOA. 
Sponges. 
Page. | Page. 
Chalina oculata..........--. 497 | Polymastia(?).-..--.-..----- 497 
Tedania, two species .....-.. 498 | Grantia ciliata...........--. 330 
Renieria, species ..........-. 330 | Leucosolenia botryoides (?).. 391 
Cliona sulphurea.........--- 421 | 
IV. 4.—FAUNA OF THE SANDY AND GRAVELLY BOTTOMS OFF THE 
OPEN COAST, 
The bottom off the southern shores of Nantucket and Martha’s Vine- 
yard is sandy or gravelly over large areas, from low-water mark down 
to 25 fathoms or more. Tracts of similar bottom occar off Cuttyhunk 
Island and farther west. In many of these places, especially in the 
shallower waters, near shore, the material of the bottom is nearly pure 
siliceous sand, varying in fineness from coarse gravel to the finest sand, 
and as these sands are generally loose and moved by the storm-waves, 
in shallow water, their inhabitants are but few. In deeper water, at 
depths of 20 to 25 fathoms or more, the material is usually a very fine 
sand, often firmly compacted, and not infrequently mixed with more or 
less fine mud. Such localities are favorable for a much greater variety 
