PORIFERA. II. 127 



Ser. 5, VII, 309, PI. XVIII, fig. 9 a— d) nothing can be said at present, and it is very doubtful whether 

 it belongs here. 



Thus the species of the genus Dendoricella will be as follows: 



1884. D. (Crella) Schmidtii Ridley, with oxea, tylota, chelae, and sigmata. 



1892. - (Damiria) cavernosa Tops, with strongyla, tylota, chelae. (Of what kind these chelae are can- 

 not be decided from the description, in which it is said a bouts pectines».) 

 1903. - (Desmacidon) abyss/ Tops, with oxea, tornota, chelae. 



- rhopaluin 11. sp. with oxea, tornota, chelae. 



- obesichela n. sp. with oxea, oxea, chelae, and sigmata. 



The Myxilla grata established by Thiele 1. c. has evidently, to judge from the figure, not 

 reallv diactinal skeletal spicules, but styli with rounded end, and is either a Myxilla or perhaps a Lis- 

 sodendoryx in the sense in which I take this genus; the fact is that it cannot be seen from the figure, 

 whether the species has chelae or aucorae. 



When Ridley referred the species Schmidtii to Cribrella = Crella, the more particular reason 

 was, I suppose, the arrangement of the pores in sieves. Characteristic as this feature may be, it is a 

 character that is found in many sponges, and cannot be used for an establishing of genera; it is only 

 a further development of the feature found in a great many sponges in which the pores are especially 

 placed over the subdermal cavities. Of Schmidt's four Cribrclla-species hamigera is now the type 

 of the genus Hamigera ; elegans, which has smooth oxea in the principal skeleton, spined oxea in the 

 dermal membrane, and further spined styli, I suppose to be identical with Topsent's genus Pytheas, 

 in which case this genus may be called Crella; liospitalis and papulosa, as mentioned by Top sent, 

 belong to the genus Yvesia Tops., which genus, what Thiele has drawn my attention to, must be 

 called Grayella Cart, with the typical species cyatophora Cart. --Of the Dendoricella-species rhopalum 

 shows the mentioned character of sharply limited pore-grooves to a strongly marked degree; the 

 structure seems to be rather similar in abyssi and Schmidtii, but it is not mentioned with regard to 

 cavernosa. 



The two species described here, and abyssi are natives of deep waters, from 799— 2596 fathoms; 

 Schmidtii and cavernosa, on the other hand, are from shallow water. 



The genus Dendoricella must among MyxillccB be the one most closely allied to the preceding 

 group, as it approaches Homceodictya ; among the Homajodictya-apecies a few are found, in which the 

 spicules of the dermal membrane are smaller than those of the skeleton, but they are of one form; in 

 Dendoricella, on the other hand, two forms are found. 



1. D. rhopalum n. sp. 

 PI. IV, Figs. 4^5. PI. XIV, Fig. 1 a-e. 

 Club-shaped, often somewhat compressed, sometimes a little lobate above. The surface with close- 

 st, more or less deep grooves, separated by ridges arranged in a net-like zvay, slightly shaggy. The 

 dermal membrane a thin film, supported by bundles of dermal spicules. Oscula more or less spout-shaped, 

 one or several, on the tipper part of the sponge. The skeleton dendritic, polyspicular. Spicula: Mega- 



