504 REVISION OF THE AXINELLIDiE, U., 



ranging from less than 300 to upwards of 500/x (occasionally to 

 upwards of 600/i) in length, and (in different specimens) varying 

 from 16 to 22/x in maximum stoutness. Microscleres: (i.)numer- 

 ous sigmata of two sizes, respectively 11 and 21/x in maximum 

 length; (ii.) trichodragmata typically of two sizes, together with 

 scattered trichites of similar length (viz., up to about 60/i,) to 

 those composing the larger dragmata; and (iii.) numerous micro- 

 strongyla, the largest measuring 20 by 8/x. 



Zoc— Off Crookhaven River, N.S.W. ("Thetis"). 

 Introductory. — In addition to the single example originally 

 described, there are now available three other complete speci- 

 mens of the species, and a fragment of a fourth. Of these, only 

 the last-mentioned is preserved in alcohol, the remainder (with 

 the exception of the type-specimen, which has been di*ied — pro- 

 bably after having been some time in alcohol — without complete 

 removal of the sarcode) being washed-out and otherwise more or 

 less damaged beach-specimens. 



External features. — In all four specimens, the general habit 

 is the same. The sponge consists of an often more or less 

 intricate cluster of erect lamellse, which are joined each to 

 another along one lateral edge, — the other edge either remaining 

 free or (less frequently) becoming connected by anastomosis Avith 

 some portion of another lamella, — and which tend most fre- 

 quently to become narrowed and more or less pointed a^ove, or 

 sometimes to partially resolve distally into several pointed digiti- 

 form processes. The iamellaj vary from 2 to 12 mm. in thick- 

 ness: and the largest specimen measures 130 mm. in height. 

 Usually, a main or primary lamella is to be distinguished, and 

 from this secondary lamellse proceed, which in turn give rise in 

 a similar way to others of higher order. The lamella? are not 

 always directed perpendicularly to those from which they arise, 

 but often more or less obliquely; and occasionally some of the 

 larger ones may be vertically curved or folded. The sponge is 

 sessile, and is sometimes attached only by a limited portion of 

 the base of the primary lamella; but more usually the area of 

 attachment is much more extensive, and is formed partly by the 

 bases of other lamellse as well. The surface is rendered more or 



