sponges. 
199 
both of large and of small size. All are smooth. The three types are (i) straight or 
feeble curved styli, (2) curved amphioxi with a median swelling and (3) curved or 
geniculate amphioxi without any swelling of the kind. 
(i) The larger spicules of this type occasionally reach a considerable size and may 
be as much as 0-348 mm. long ; but this is exceptional. They are not less than 23 
times as long as broad. The head is not at all dilated but abruptly rounded; the 
diameter of the spicule is uniform for about f of its length. The tip is gradually and 
sharply pointed. The smaller spicules of this type are from 015 mm. to 0 3 mm. long 
and have similar proportions to the larger ones. Occasionally the)^ bear a median 
swelling. Styli of all kinds are scarce. 
{2) The proportion of amphioxous spicules with a median swelling is small. I 
have not been able to find geniculate spicules of this type. lyarge amphioxi with the 
swelling are sometimes as much as 0-44 mm. long, but often not more than 0 2 mm. 
They are from 24 to 25 times as long as broad, omitting the swelling. The extremities 
are sharply and gradually pointed. 
(3) The majority of the spicules are of this type, slender, amphioxous, curved 
or geniculate, without median swelling. The proportions of geniculate spicules is 
small, but such spicules occur among both the large and the small amphioxi. The 
length is from 26 to 33 times as great as the maximum breadth and the extremities 
are sharply and gradual^ pointed. 
Abnormal spicules with one extremity angulate are not uncommon among those 
of larger size. 
Type-specimen. No. ZEV. 7137/7, Zool. Survey of India {Ind. Mus.). 
Locality. Port Weld, Perak, Malay Peninsula : between tide-marks on a landing- 
stage in a salt-water creek some miles up from the Straits of Malacca. 
This sponge is distinguished from the two varieties of A . excavans already des- 
cribed by Carter {op. cit.; 1887) and myself {op. cit. ; 1915) mainly in external structure. 
There are, however, slight differences in the spicules. 
II. FRESHWATER SPONGES FROM JAPAN, CHINA AND THE 
MALAY PENINSULA. 
A. Japanese Species. 
The archipelago of Japan is still to a large extent unexplored so far as the Spon- 
gillidae are concerned and only two of its numerous lakes have been investigated. 
These lakes are Lake Biwa in the interior of the Main Island and Kasumi-ga-Ura on 
the Pacific coast of the same island. The sponges of Lake Biwa have recently been 
discussed in considerable detail by Dr. T. Kawamura and myself, and no species which 
does not occur in the lake has been found elsewhere in Japan. The only form in which 
this is the case is the forma typica of Ephydatia mulleri, which has been found at 
Tokyo, but in neither lake. It will be sufficient here to give a list of the known 
Japanese species and to publish an adequate diagnosis of a new form incorrectly identi- 
fied in the former paper. 
