146 
PACIFIC SCIENCE, Vol. XIX, April 1965 
Fig. 11 a. Euryspongia lobata n. sp. Holotype. 
usnm 23710. Sta. 220. 
SURFACE: Coarsely conulose, with sandy det- 
ritus arranged in close-set lines diverging from 
each conule. 
Conule Height 
(mm) 
Conule Spacing 
(mm) 
Oscules 
(mm) 
Sta. 100 
. 1.5-4. 0 
1. 0-5.0 
1. 0-2.0 
lateral 
Sta. 220 
(Type) 
. 1.0-3. 5 
1.0-5. 5 
1. 5-3.0 
lateral 
In the interconular areas the pattern of the 
surface detritus becomes netlike. 
SKELETON: In features of the skeleton this 
species is somewhat intermediate between Dysi- 
dea and Euryspongia . 
The primary fibres are cored with spicule 
debris and are slightly fasciculated. Secondary 
fibres arise more or less at right angles, are 
much branched forming rounded meshes, and 
often include spicule fragments. These never 
form a continuous core and are not a constant 
feature of the secondary fibres. The spongin 
shows no sign of concentric lamination. 
Primary fibres are 86-125/* (108 /*) in di- 
ameter, secondaries are 37-57/* (42/*). 
ECTOSOME: The thin dermal membrane con- 
tains abundant sandy debris which does not 
extend into the cortical region. The latter is a 
compact layer, 30-60/* deep, of collagenous tis- 
sue containing isolated branched cells and abun- 
dant symbiotic blue-green algae. 
ENDOSOME: Flagellate chambers are abun- 
dant, large, oval, and eurypylous, 75-90/* X 50- 
62/*. Collagenous tissue containing spindle- 
shaped cells and algae surrounds the groups of 
chambers and lines the larger canals. 
DISCUSSION: Coring material extends into 
the secondary fibres of this sponge and in this 
regard it resembles a Dysidea. In all other fea- 
tures, however, it is more typical of Eury- 
spongia . 
Euryspongia lobata is not particularly close 
to any other species described thus far in this 
genus. The surface conules are larger, the pri- 
mary fibres finer and slightly fasciculate, the j 
fibre reticulation more compact. Except for its j 
300 // 
Fig. 11 b. Euryspongia lobata n. sp. Portion of the f 
fibre network. 
