A. EF. Verrill—The Bermuda Islands; Geology. 147 
Annelids of many kinds* also swallow the mud and sand with 
little selection, while others pick out, with their prehensile organs, 
the small living mollusks, etc. Among the larger forms burrowing 
in the sand are Arenicola cristuta (fig. 41) and Ewpolymnia mag- 
nifica (plate xxxv, fig 1, a); also the “ blood-drop ” Enoplobranchus 
sanguineus Ver. 
The first is often 12 to 15 inches long and nearly an inch in 
diameter. Its color in life is dark olive-green or blackish green, 
with dark red plumose gills. It is common on most of the sandy 
bottoms in shallow water and at low tide. It makes large and deep 
burrows, which often have large coils of mucus at the entrance. 
The second is nearly white, with a body more than a foot long. Its 
Figure 41.—Arenicola cristata; a, profile; 6, dorsal view; 1g natural size ; 
Phot. by A. H. Verrill. 
numerous white, slender, prehensile tentacles, which spread out in 
every direction, are often more than a foot long. Its intestine is 
usually so filled with mud and sand that the delicate walls of the 
body will burst when it is taken from its burrow. It builds in the 
burrow a large and rather delicate tube usually consisting mostly 
of small bivalve shells, both entire and broken, loosely cemented 
together. The tube is concealed in the sand or under stones in 
sandy places. It selects such materials with its tentacles and puts 
them in place with the same organs. 
* Many of the annelids were described by me in these Trans., vol. x, pp. 
595-670, 1900. 
