A NEW GENUS OF SYNASOIDIANS FROM JAPAN. 321 
two sub-genera, viz. Leptoclinum proper, characterised by its 
thin encrusting cormi; and Didemnoides, which is qualified as 
follows :—‘‘ Fleischiger Cormus, in Polstern oder Knollen.” 
Von Drasche describes and figures two species of Didemnoides, 
viz. D. macroophorum and D. resinaceum. 
There can be very little doubt that we are right in allying 
our new genus with the Didemnoides of von Drasche, while 
the extraordinary habit of growth of our new form unques- 
tionably calls for the formation of a new genus. As Della 
Valle (4) indicates, the thickness of 3 cm. is very great for a 
Didemnid, while our Didemnid attains a thickness of over 
6 cm.! Perhaps the most striking feature of the new genus is 
the lateral compression which it exhibits (see fig. 2). 
7. Summary. 
Sarcodidemnoides misakiense, Oka and Willey. 
Generic Characters.—Colony (or cormus) forming very 
thick lobose masses, laterally compressed ; sessile, but not 
encrusting. 
Excurrent orifices placed on the tips of the knoll-like 
prominences. 
Ascidiozooids very numerous, not arranged in systems ; 
branchial sac with four rows of stigmata; canal system com- 
plicated, differentiated into peripheral and central portions. 
Specific Characters.—Atrial apertures of Ascidiozooids 
simple pores without teeth or languet; spicules fairly abun- 
dant, extremely delicate, confined to a thin layer near surface 
of test. 
Test gelatinous, containing numerous bladder-cells, crystals, 
fusiform cells, and pigment concretions. 
Stomach of Ascidiozooids vertically placed; surface of 
attachment of colony narrower than the free portion. 
Colour, brilliant red. 
Habitat.—Moroiso, Japan, between the tide-marks. 
1 Von Drasche (p. 32) mentions a species of Didemnum—D, tortuosum 
—which attains a thickness of 5 cm. 
VOL. XXXIII, PART II.—-NEW SER. Y 
