456 " THETIS " SCIENTIFIC RESULTS. 



PACHYOHALINA PEDUNCULATA, Lendenfeld, sp. 



Plachochalina pedunculata, Lendenfeld, Zool. Jahrb., ii., 1887,, 

 p. 791 ; Austr. Mus. Cat., xiii , Sponges, 1888, p. 90. 



Cavochalina hilamellata (Lamk.), Carter, Ann. Mag, Nat. Hist.,. 

 (5), xvi., 1885, p. 287. 



Pachyihalina hilamellata (Lamk. 1), Carter; Dendy, Proc. Roy. 

 Soc. Vict., n.s., vii., 1895, p. 242. 



Stations 4, 48. 



The late Mr. H. J. Carter first described this species from Port 

 Phillip. At the time he thought it was identical with Spongia 

 hilamellata, Lamarck, and named it accordingly. Previous to 

 this Ridley* had examined a fragment of Lamarck's " original 

 type specimen," and redescribed the Lamarckian species as 

 Echinodictyum bilamellatum. 



Pachychalina pedunculata, Lendenfeld, was published as an 

 ideal species consisting of three varieties, which prove to be 

 identical with Carter's sponge, and since they can no longer be 

 considered as hilamellata, Lamarck, Lendenfeld's name must 

 stand ; the three varieties may be enumerated as follows : — 



(1) P. jndunculata, var. dara, Lendenfeld. This variety is by 

 far the most common, and usually consists of a short, stout stem 

 surmounted by a pair of flabellate expansions. The dermal surface 

 is smooth, close and compact, with discernable pores on the inner 

 aspect, but it requires a lens to see those on the exterior. The 

 lamellae are about 8 or 10 mm. in thickness, and are ornamented 

 with concentric growths internally ; the outer surface presents a 

 series of meandering ridges and wart-like prominences from 2 to 

 10 or more mm. in height. The spicules are slightly curved 

 sharp pointed oxea 0-06 to 0065 by 0.004 mm. 



(2) P. pedunculata var. jjocula, Lendenfeld. This form is 

 narrowly cup-shaped, with the walls of the cup from 1 to 4 mm. 

 in thickness The external surface is furnished with warts and 

 wavy ridges, but they are rarely more than 2 or 3 mm. high, and 

 at the distal sixth they fade away. The spicules are curved oxea 

 OOi to 0-07 by 004mm. 



(3) P. pedunculata var. mollis, Lendenfeld. This variety 

 forms a very shallow cup with a well defined peduncle. The 

 outer surface presents an irregular series of ripple or wave-like 

 markings ; the crests of the waves are generally acute and from 



* Bidley— Journ. Linn. Soc, Zool., xv., 1881, p. 493, pi. xxviii., figs. 1-6- 



