186/.] DR. J. E. GRAY ON SPONGES. 529 



to say, in those that have an irregular edge to the upper part of the 

 tube, or other deformities of growth. 



Euplectella, Owen, Trans. Zool. Soc. iii. p. 203, 1841. 

 Alcyoncellum, Bowerb. B. Sp. i. p. 176 (not Blainville, nor Quoy 

 and Gaimard). 



The texture of Eu2')lectella has been compared to woven lace. 

 The threads of the Euplectella were not first spun and then inter- 

 woven as in the case of human manufacture, but were formed as 

 interwoven, the two processes going on simultaneously, ov pari passu; 

 and this is further shown by the fact that, in a specimen that had 

 been pierced, the hole is filled up with interwoven fibres like a 

 darn. It is to be recollected that the beautiful object which we have 

 in our cabinet is but the skeleton of the sponge ; and in its living 

 state this exquisite flinty framework is veiled by a delicate gela- 

 tinous enveloping organic tissue (see Owen, Trans. Linn. Soc. xxii. 

 p. 121). 



1. Euplectella aspergillum, Owen, Trans. Zool. Soc. iii. 

 p. 203, t. 13 (upside down). B.M. 



Euplectella speeiosa, Gray, Ann. & Mag. N. H. 1866, xviii. p. 487. 



Alcyoncellum aspergillum, Bowerb. B. S. i. p. 177, f. 174, 17/), to 

 p. 184, f. 186, 189, 193, 194, 198, 253, 356, 357. 



Hah. Philippine Islands (^Cuming). 



This species is liable to several variations ; its form is sometimes 

 short, ovate, and straight like the following ; the regular longitudinal 

 and transverse bundles of spicules are distinctly marked, indeed 

 more so in the young specimens only a few inches long than in the 

 adult. 



There is a good series of varieties of different ages in the British 

 Museum. 



2. Euplectella cucumer, Owen, Trans. Linn. Soc. xxii. p. II 7, 

 t. 21 ; Bowerb. B. S. i. p. 237. f. 59. 



Hab. Seychelle Islands (Capf. Etheridge). 



Only known from the single specimen in the collection of Dr. 

 Farre. The absence of the fringe and the small size of the transverse 

 ridges may be dependent on the age or imperfect development of the 

 specimen, for that is the peculiarity of the younger specimen from 

 the Philippines. 



I have not seen the specimen ; but Dr. Bowerbank, who has exa- 

 mined it and its spicules, informs me that he regards it as only a 

 variety of E. aspergillum ; but the difference in the locality and the 

 peculiar form leads me to believe that it is a distinct species ; and I 

 hope Dr. Perceval Wright, who has gone to the Seychelles to study 

 the natural history of those little-known islands, will bring home 

 specimens that may determine this and other interesting zoological 

 questions. 



Proc. Zool. Soc— 1867, No. XXXIV. 



