PORIFERA. II. 109 



not been taken here, but at the entrance to the Strait of Gibraltar. According to these facts Carter 

 has surely been mistaken, and the species belongs to the latter locality. The branched forms of sponges, 

 which are mentioned by Wyville Thomson (Proceed, of the Roy. Soc. XVIII, 443) from station 52, 

 1869, and which led Carter to refer C. virgata, for which he found no locality, to this locality, are 

 surely the Cladorhiza-ioxms taken here. 



The genera Chondrocladia and Cladorhiza are closely allied to each other, and the distinction 

 between them is exclusively founded on the difference between the inequi-ended ancorse and the equi- 

 ended ones. As in the Asbestopluma-species, embryos are, as will have been seen, almost always found 

 in the species of these two genera. Of C. abyssicola Sars has stated that the embryos are formed in 

 the point of the branches, and in C. tenuisigma I have found that the spermatozoids are formed in 

 the swollen ends of the branches. My examinations, however, are too insufficient to decide whether 

 the sexual products are always and exclusively formed in the ends of the branches, but it seems pro- 

 bable. In this connection it is to be remembered that in almost all the species a particular sigma 

 occurs, exclusively or chiefly belonging to the swollen ends of the branches. Whether there is any 

 connection between these two things, whether this sigma here may possibly have a special function, I 

 dare not, however, to decide, but it seems only to be formed in the swollen ends of the branches, that 

 is to say, in the place where also the sexual products are formed. In C. iniquidentata no such sigma 

 was found. — That embryos are always found in these forms, which all are deep-sea species, may 

 perhaps be accounted for by the fact that the embryos are not developed during any definite time of 

 the vear, but all the vear round. 



The Chondrocladia-species, like the Cladorkisa-sipecies, are forms that live in rather deep water, 

 but upon the whole they do not seem to reach so great a depth as the Cladorhiza. The vertical 

 distribution of the species reaches from 130 fathoms, at East-Greenland, to 2900 fathoms, in the northern 

 Pacific, but of the nine known species only three live in depths of 200 fathoms or more. The genus 

 is distributed from about 66° Lat. N. to 19 06. Lat. S. 



The species of the genus are the following: 



1873. C - virgafo Wyv. Thorns. The Strait of Gibraltar. 



1880. - (Cladorhiza) concrescens O. S. The West Indies. 



1SS0. - (Crinorhiza) amphiactis O. S. Barbados. 



1885. - (Desmacidon) gigantea Arm. Hans. 



1887. - concrescens? O. S., R. and D. The northern Pacific. 



1887. - clavata R. and D. The Fiji Islands. 



1887. - crinata R. and D. North of Guinea. 



