PORIFERA. II. 



43 



consequently will have these referred to the chelae, his theory is of no importance. Carter mentions 

 and figures rosettes; I have also seen such, but the}' were less distinct than elsewhere in Mycale-species. 

 In the rosette the chelae have the end with the larger tooth turned towards the middle of the rosette. 



2. Sigmata. They are of a regular sigma-form; the ends are with a round curve bent round 

 to about a right angle. They are plane or slightly contort; especially the smaller forms are contort, 

 while the larger ones are most frequently quite plane. They are very much varying as to size, and 

 may be rather large. The length varies from 0-05 — ci^ 1 ", and the thickness proportionally from crooi8 

 — o-oo57""". The measures given by Schmidt, are, no doubt, due to an error. As well chelae as sig- 

 mata occur everywhere in very large numbers. 



In spite of the peculiar chelae of this species, I have placed it under the genus Mycale, because 

 the chelae must be referred to the type anisochelae palmatce, and its skeletal structure being hitherto 

 only imperfectly known, I have thought it most convenient to keep it in this genus. 



Locality : Station 78, 6o° 37' Lat. N., 27° 52' Dong.W., depth 799 fathoms; station 97, 65° 28' Lat. N., 

 27° 39' Long. W., depth 450 fathoms. The former station is on the eastern slope of the Reykjanaes-ridge, 

 the latter in the Denmark Strait. Altogether we have only four fragments. 



Geogr. distr. Florida, depths 174 — 324 fathoms (Schmidt). 



6. M. intermedia O. Schmidt. 

 1874. Espcria intermedia O. Schmidt, Die zweite deutsche Nordpolarfahrt, II, 2, 433, Taf. I, Fig. 40. 

 1903. Mycale intermedia Thiele, Arch, fur Naturgesch. 1903, 381, Taf. 21, Fig. 12. 



This species I have not had before me. It would not be possible to recognize it by Schmidt's 

 description, but Thiele has I.e. given a new description of it. Of spicules it has the following forms: 

 a. Megasclera oxea, ca. o4-5 mm long and o-oio— croi2 mm thick; b. Microsclera large anisochelae palmatae 

 in rosettes, 0-05— o-o6 ,nm long, with the smaller end rather large; small anisochelae palmatce ca. croi8 mm ; 

 the latter do not form rosettes. 



This species deviates from all other Mycale-species by its diactinal megascleres; Thiele there- 

 fore says that there may possibly be some reason for separating it from the genus Mycale, but this 

 he will not do, however, as long as only this one species is known, and in this I follow him. 



Locality: Northern East-Greenland. 



Asbestopluma Norman. 

 Erect, stalked forms; t/ic upper part penniform, or with side-branches issuing from all sides of an 

 axis or collected at its upper end, or the sponge formed like a long-stalked cup. The skeleton is exactly corre- 

 sponding to the form, and consists of a- spicula-axis often divided info parallel fibres ; in this axis is in- 

 serted fibres running one through each side-branch. Sometimes a coat with particular, densely interwoven 

 spicules on the stalk. In the skeleton of the axis spongin is found. Spicula ; Megasclera monactinal, 

 slyli or subtylostyli, and, where a coat is found on the stalk, in this coat minutely sptned tylostyli or 

 tylostrongyla ; microsclera: the characteristic microsclera arc small anisochcla' palmata- of a peculiar form, 

 with a strongly marked contrast between the two cuds; to these may be added larger anisochcla' palmata- 

 and sigmata, or only sigmata or forcipes. 



6* 



