4 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 1 1 



Oscules, which vary in size from about 1,500 to 2,500 fx in diameter, 

 are irregularly scattered over the surface. The pores are not visible to 

 the naked eye. 



Flagellate chambers are usually about 25 by 35 /x, but occasional 

 smaller ones are observed. They are diploidal, as is characteristic of the 

 family. 



Ascending fibers average 150 ju in width, but vary between 120 /x and 

 165 IX. The tangential fibers very between 70 and 125 /x with an average 

 near 100. 



Holotype. — AHF no. 1. 



Type locality. — Isabel Island, Sinaloa, Mexico; pontes coral; 4 m. 



Distribution. — Gulf of California. 



Material examined. — 

 Sta. 125-33 Isabel Island 3-19-33 4 m 



Remarks. — The specimen dififers from most of the genus in that it 

 does not have sand particles at the nodes and also in that it has both 

 relatively very large secondary fibers and very large amounts of detritus 

 in the primary fibers. 



It is most like the sponge first described as Holopsamma laminae- 

 favorsa. Carter 1885, from Australia, but that sponge had a smooth 

 ectosome, whereas the Hancock specimen possesses conspicuous cornules. 

 Furthermore, H. laminae-favorsa had main fibers made up of sand grains 

 with little spongin and tangential fibers only 16 ju, wide. H. hancocki has 

 a large amount of detritus irregularly placed in the primary fibers but 

 no sand grains at the nodes, much spongin, and exceptionally wide tan- 

 gential fibers ( 100 /x as compared to 16 /x average) . 



Genus HIRCINIA Nardo 

 Hircinia fusca Carter 



Plate 3, Fig. 5 



Hircinia fusca Carter, 1880, p. 36. 



Diagnosis. — This sponge has a ramose to digitate shape, is brown in 

 life, and is rather firm in consistency. 



The principal tracts have a diameter of 100 to 180 ^a and have much 

 detritus. The mesh of the fibers is about 1,000 jx in diameter. Filaments 

 are abundant and average about 3 /x in thickness. 



Holotype. — Liverpool Free Museum. 



Type locality. — European waters. 



Distribution. — Cosmopolitan. 



Material examined. — 

 Sta. 650-37 San Fransisco Island 3- 9-37 92 m 



