BY E. P. KALLMANN. 639 



Genus Dragmacidon, gen.nov. 



Definition. — Axinellidpe of more or less massive ' habit, some- 

 times provided with incipient eonuli, but without surface-processes 

 of other kind. The skeleton consists of irregular plumose columns 

 loosely composed of mingled oxeote and stylote megascleres or of 

 oxea alone, and of (sometimes relatively scarce) connecting fibres 

 formed of the same spicules; typically, spongin is developed in 

 connection with the fibres rather sparinglj^, and there is no 

 dermal skeleton. In addition to the oxea and styli composing 

 the skeletal columns, — which typically are of similar or nearly 

 similar dimensions, — longer megascleres of a single kind (likewise 

 either oxeote or stylote) may occur interstitially. The micro- 

 scleresare trichodragmata, accompanied or not by single trichites. 



Type-species, D. agaricifcn'inis Dendj'iS). 



Besides the type-species, the genus will include Dendy's Thrina- 

 cophora dvrissima (which likewise comes from Ceylon), and the 

 species originally described by Lendenfeld, from Port Jackson, 

 as Halichondria clathriformis.* The last-mentioned, — a rede- 

 scription of the skeletal characters of which, based on a small 

 piece of the type-specimen received from the British Museum, 

 has recently been given by me(l3), — is distinguished by the fact 

 that its megascleres are almost exclusively oxea; and on that 

 account the propriety of its association in a single genus with 



"Subsequently I have found that Whitelegge's Giocalypta incrnstan»{58), 

 from Funafuti, constitutes a fourth species of this genus. In this, as in 

 D. diiri.s-sima, special interstitial megascleres are wanting and the spicula- 

 tion consists of styli and oxea in about equal number occurring in the 

 skeleton promiscuouslj^ intermingled; but the styli are here larger than 

 the oxea, ranging in length from less than 200 to upwards of 550/x and 

 occasionallj' attaining to 13/;, in stoutness, while the latter rarely if ever 

 exceed a size of 400 by 10/;.. The oxea are exactlj^ similar in shape to 

 those of the three species of AHantophora described above, and (as in the 

 same species) are not connected with the styli by intermediate forms. The 

 stiucture of the skeleton closely resembles that lioth of D. ayarlclformis 

 and D. dathriformis. The trichodragmata, which are ver3' scarce, have 

 the form of stout compact bundles 12 to 14/x in length. Singly scattered 

 ti'icliites do not occur. 



