SPONGES FKOM THE ABROLHOS ISLANDS. 503 
The spiculation agrees closely with that of Pseudoesperia carferi, except 
that the sigmata are entirely replaced by trichodragmata. 
Spicules : — (1) Tylostyli ; size about 0'34 by 0'006 mm. 
(2) Large, quadridentate auisochelse ; about 0"056 mm. in length. 
(3) Small, semi-bipocillate anisochelas, about O'Ol mm. in length. 
(4) Small, palmate anisochelse, about 0'012mm. in length. 
(5) Trichodragmata ; short, compact bundles, measuring about 0'026 by 
0-006 mm. 
It is an interesting fact that this species differs from Pseudoesperia 
carteri only in the replacement of the sigmata of the former by trichodrag- 
mata. These spicules are so widely and so sporadically distributed throughout 
the tetraxonid sponges that it is extremely difficult to estimate their taxonomic 
value. 
The peculiar form of the quadridentate anisochelse and the occurrence of 
what we have called the " semi-bipocillates " seem to justify the retention of 
Carter's genus Pseudoesperia. 
Register No. and Locality. II. 12 a, Wooded Isle. 
34. EsPEKELLA PLUMOSA {Carter). 
(For literature and synonymy vide Dendy ( 1916 A].) 
The material consists of a small, whitish-yellow fragment encrusting Hippo- 
spongia intestinalis (Lamarck)- No further description is necessary. 
Previously known Distribution. Mauritius and M ergui Archipelago ( Carter^ ; 
Ceylon, Okhamandal {Dendy'). 
Register No. and Locality. VI. 13 h, Sandy Isle. 
35. BiEMNA TUBULATA Dendy. 
Desmacella tubulafa Dendy [1905, 1916 A]. 
Biemna microxa Hentschel [1911]. 
Toxemna tuhulata Hallmaun [1917]. 
Biemna tubulata Dendy [1921 B]. 
The material consists of a couple of fragments of thin-walled tubes, the 
outer surface of which appears slightly granular, while the inner bears 
numerous minute openings of exhaknt canals. C!olour in spirit brownish 
yellow ; texture very soft and fragile. 
The skeleton arrangement and spiculation agree very closely with those of 
previously described specimens. 
We consider Biemna microxa Hentschel [1911] to be identical with this 
species. 
Previously known Distribution. Grulf of Manaar, Okhamandal, Indian 
Ocean [Dendy) ; S.W. Australia {Hentschel). 
Register No. and Locality. VIII. 3, Sandy Isle. 
