REPORT ON THE MONAXONIDA. 31 



Siphonochalina anmdata, Ridley and Dendy (PL YII. fig. 2). 



1886. SiphonocJiaUna mmulata, Eidley and Dendy, Ann. and Mag. Nat. Hist., ser. 5, vol. xviii. 



p. 331. 



Sponge (PI. VII. fig. 2) rooted, stipitate, ramose. Branches long, tubular, rather 

 slender, very distinctly annulated, often anastomosing with one another. Mode of branch- 

 ing irregular. Root large and much branched ; stem short and slender. The laro-est 

 specimen measures about 300 mm. in total height, including the root. The branches 

 average a little over 12 mm. thick at the centre of each joint ; and each joint is commonly 

 a little less than 12 mm. long, though in this respect there is considerable variability. 

 Colour in spirit doubtful (now a rusty red, but this may be due to the specimen having 

 been packed in an iron box). Texture soft and spongy, but tough and fibrous. Surface 

 glabrous. Dermal membrane very thin and transparent, firmly adherent to the underlying 

 tissues. Oscida ; there is one large circular osculum at the summit of each branch. 



Skeleton. — (a) Dermal; a reticulation of rather stout spiculo-fibre, containing a very 

 large proportion of horny matter and few spicules, abundantly echinated by outwardly 

 projecting tufts of spicules. (6) Main; a feebly-developed, subrectangularly-meshcd 

 reticulation of spiculo-fibre, about 0'07 mm. in diameter, cored by spicules arranged poly- 

 serially ; the rectangular character of the reticulation, as is very commonly the case, 

 becomes lost in the deeper parts of the sponge. 



Spicules. — Slightly curved, suljfusiform oxea, sharply and rather gradually pointed, 

 measuring about O'l by 0'0065 mm. 



The most characteristic feature of this species is its external form, and more especially 

 the extent to which the annulation of the branches, a not uncommon feature in Chalinine 

 sponges, is carried. It is distinguished by this character and by the greater length of 

 the branches from Siphonochalina tubulosa, Esper, and Siphonochalina intermedia, nobis. 



Xoca%.— Station 162, April 2, 1874; lat. 39° 10' 30" S., long. 146° 37' 0" E. ; 

 Bass Strait ; depth, 38 fathoms ; bottom, sand and shells. Two specimens. 



Family II. Heterokrh aphid ^e.^ 

 1886. HeterorrliapMdx, Ridley and Dendy, Ann. and Mag. Nat. Hist, ser. 5, vol. xviii. p. 332. 

 Megasclera of various forms ; microsclera commonly present, but never chelae. 



Subfamily 1. Phl(eodictyiN/E. 



1882. Phlmodictyina, Carter, Ann. and Mag. Nat. Hist., ser. 5, vol. x. p. 117. 



Sponge massive, consisting of a central, usually more or less globular, solid bodj^, with 

 closed (? or open) tubular processes (fistulse) projecting from it. Free or attached. With 

 a well-marked external rind, composed of an outermost, thin but distinct, transparent 



' iTifos, different ; pa.(pis, needle. 



