Holothurians allied to Cucumaria frondosa (GUNNER). 607 
a range from 0,4—3 mm. In the very young the madreporite is 
composed of 2 or 3 simple lobes (Fig. 21). The madreporites of the 
accessory stone-canals are almost constantly spherical in form having 
a mean diameter of 0,6 mm with a range from 0,4—1,1 mm. One 
exceptional madreporite is elongated and 5 mm in length. 
In the gonads, respiratory trees, muscles and enteric canal this 
species agrees with Cucumaria frondosa. 
Habitat. — Pacific coast of North America from Southern 
California to Cedar Island, Alaska. 
Localities ofthe 35specimensin the United States 
National Museum. — 33° 3845“ north latitude, 118° 13° 45“ 
west longitude, depth 20 fathoms. Sand Point, Humboldt Bay, Cali- 
fornia. 48° 8°10“ north latitude, 122° 41‘ 48" west longitude, depth 
15—26 fathoms.. Port Townsend Bay, Washington. Neah Bay, 
Washington. Puget Sound, under rocks, low tide. Straits of Fuca. 
Ottar Bay, Pender Island. 54° 13' north latitude, 163° 06° west 
longitude, off Unimak, south of Alaska Peninsula, depth 38 fathoms. 
Öedar Island, Loring, Alaska. Off Shakan, Summer Strait, S. E. 
Alaska, depth 169—212 fathoms. 
Cucumaria fallax Lupwic. 
1874. Cucumaria fallax LUDWIG. 
1881. Oucumaria miniata LUDWIG. 
1906. Cuceumaria miniata BRITTEN. 
In most of its characters this holothurian closely resembles 
Cucumaria frondosa but it is differentiated from that species by the 
size, spicules (including forked anal teeth) and Polian vesicle and 
from Cucumaria miniata besides especially by the presence of only 
one stone-canal. I have examined the specimens placed by BRITTEN, 
1906, under Cucumaria miniata and am convinced of their identity 
with Cucumaria fallax. 
Size in centimeters. — The 39 specimens seriated have a 
mean body-lenseth of 5, with a range from 2,4—8,6 and a mean 
dorso-ventral diameter of 2,1, with a range from 1—3. The anterior 
part of the body introverted has a mean length of 1.2. 
Tentacles. — Ten, large and equal. One variate has 11, 
the extra tentacle being a second to the left from the mid-ventral 
radial canal. 
Genital papilla. — In the female the genital papilla is 
