SPOXGES FROM COASTAL BEACHES OF N. S. "WALES— "WHITELEGGE. 87 



Thalassodendron rubens, var. dura, Lendenfeld, (No. 343). 



This variety differs from the typical form, and also from the 

 following variety, in having a greater number of echinating styli; 

 they are longer, sharper pointed, and less spiny than in T. rubens 

 or in the variety lamellosa, and I failed to find any smooth styli 

 echinating the fibres. The projecting smooth spicules were observed, 

 but they are incipient secondary fibres with one or two smooth 

 stylote spicules. 



Megascleres — (a) Spined styli, very numerous. Size — 0'08 to 

 01 by 0006 mm. (5) Smooth styli. Size— 0-27 by 0-005 mm. 

 (c) Smooth styli. Size— 02 by 0002 mm. 



Microscleres — Chelae 0-0014 mm. in length. 



Thalassodendron rubens, var. lamellosa, Lendenfeld, (No. 432). 



In the figured type the spicules generally are fewer than in the 

 typical form. The description states that the echinating styli are 

 " pretty scarce." 



Megascleres — {a) Spined styli, very scarce. Size — 0-05 by '0045 

 ram. (6) Smooth styli. Size — O'l to 0-16 by 0'006 mm. (c) Smooth 

 styli. Size— 0-8 by 0-0015 mm. 



Microscleres — Chelte O'OOl mm. in length. 



Thalassodendron brevispina, Lendenfeld, (No. 361). 



This form does not differ materially from T. rubens, var. dura, 

 except in the size of the spicules. 



Megascleres — (a) Spined styli. Size — 0-03 by 0-005 mm. 

 (b) Smooth styli. Size— 0-18 by 0-0065 mm. (c) Smooth styli. 

 Size— 0-25 by 0-0015 mm. 



Microscleres — Isochelse 0-008 in length. 



Thalassodendron paucispina, Lendenfeld, (No. 360), 



In habit this form resembles T. rubens, and in its spicular 

 characters agrees with the preceding, excepting that the echinat- 

 ing styli are more spiny and less acute. 



Megascleres — (a) Spined styli. Size — 0-04 by 0-006 mm. 

 (b) Smooth styli. Size— 0-18 by 0-008 mm. (c) Smooth styli. 

 Size— 0-1 by 0-002 mm. 



Microscleres — Isochelse 0-008 mm. in length. 



Thalassodendron viminalis, Lendenfeld, (No. 365). 



The type does not accord with the description. The latter 

 states that : " The sponge consists of a number of pretty regular 

 cylindrical upright branches which are not much branched." The 

 example in the collection bearing the above name and number, is 

 clathrate and consists of a series of short flattened branches, from 

 4 to 20 mm. wide, 2 to 4 mm. thick, and from 5 to 30 mm. long, 

 The lamellae have their edges directed outwards ; towards the 

 centre and at the sides they exhibit frequent coalescence, the 



