408 REVISION OP THE MOKAXONID SPONGES, ill., 



towards the base than at the middle. They measure from 220 /a 

 to 295 /x in length and are seldom as much as 5 /x in diameter. 



(b) The anisochelse are of the ordinary form; they are variable 

 in stoutness and range in length from 18 to 27 /tx. 



(c) The sigmata are very slender, seldom much more than 1 /x 

 in diameter; they are simple and contort, and vary from 18-5 to 

 29 /x in length, measured from bend to bend. 



(c?) The trichodragmata are 12 to 2b fi long, and usually less 

 than 5 /x in stoutness. The trichites composing them are some- 

 times partially fused, so that the dragma remains intact even 

 after boiling in nitric acid, and are sometimes differentiated into 

 separate microxea. Microxea also occur scattered singly, but as 

 such are extremely rare. 



Embryos. — The examined portion of the sponge teems with 

 aspiculous embryos of approximately spherical form, the largest of 

 which measured 150 /x in diameter. 



Log. — Port Jackson. 



Remarks. — The species that seems most closely related to M. 

 serpens is M. fistulifera Row(35). In the latter, trichodragmata 

 have not been observed and the processes bear each an osculum 

 at the summit. If similarly located oscula occur in M. serpens, 

 they must be extremely small; but I am unable to say positively 

 they are absent, owing to the poor preservation and pulpy con- 

 dition of the specimen. 



EsPERELLA PENiciLLiUM. (Pl.xxiv., fig.l; and text-fig.l5). 



Introductory. — As the specimen which I take to be the type 

 of this species is not entirely in agreement with the description 

 of the species, I might mention that its claim to be so considered 

 is proven, both by the fact that it is labelled in Lendenfeld's 

 handwriting with a manuscript name — " Esperia incrustans'^ — 

 which according to the key-list stands for Esperella periicillium — 

 and by the fact, also, that it agrees in all essential respects with 

 a British Museum specimen labelled Esperella penicillium. The 

 species belongs to the subgenus Paresperella and is related to 

 F. moluccensis Thiele(41), /^ bidentata Dendy(15), F.repens White- 

 legge(57), and F. dichela Hentschel{20)— apparently more closely 



