BY E. F. KALLMANN. 271 



British Museum; though among the sponge-fragments whicli have 

 been received from that Institution none labelled as T. multistella 

 are included. 



The following brief descriptions of the several forms above 

 mentioned — whicli on account of their surface-tessellation and 

 their spiculation, could, I suppose, be designated varieties of 

 Donatia lyncuriwrn — a.ve intended merel}'^ for the purpose of 

 indicating the chief reasons against the acceptance of any of 

 them as an example of the species here in question. 



i. This sponge, which is a common one in Port Jackson and 

 adjacent localities in shallow water, is represented by a number 

 of specimens. The spicules of the radial fibres are styli, which 

 are generally sharp-pointed, and attain a size of about 1250 by 

 16 ix\ the terminal spicules of the fibres project only a slight 

 distance beyond the surface. Between the fibres in the outer 

 region of the choanosome, fairh^ abundant radially directed 

 slenderer megascleres occur, and in the spicular "nucleus" of the 

 sponge are found comparatively short styli, some of which are 

 less than 200 /x in length, Spherasters occur only in the cortex, 

 and are comparatively very scarce even there; they are at most 

 45 /x in total diameter, and are provided with straight, conical, 

 smooth rays, the length of which may attain to three-fourths the 

 diameter of the centrum, and the number of which (actually 

 countable) varies from 14 to 18, Tylasters are plentiful in all 

 parts of the sponge, most abundant in the superficial layer of the 

 cortex; they seldom exceed 15/x in diameter and have the 

 slightly expanded extremities of the rays minutely spined. 



ii, A single specimen, labelled as from Port Jackson, is remark- 

 able in having spherasters, the surface of the rays of many of 

 which is roughened with incipient spines; occasionally a few of 

 the spines are of considerable size. In other respects this sponge 

 is very similar to the preceding; but the styli attain a stoutness 

 of 20 /x, and the spherasters a diameter of 55 /y.; the length of the 

 rays of the latter ma}^ equal the diameter of their centrum; and 

 the tylasters are rare in the choanosome, except in the inmie- 

 diate surrounding of canals. 



