Sponges from South Australia. 109 



even ; with small elevations and close reticulated tissue. 

 Pores in the interstices of the reticulation. Vents large, 

 disposed in line, along the round end. Internally cavernous, 

 from the parenchyma of the Esperia being chiefly confined to 

 the sand-cored fibre of the old Psammonematous structure. 

 Spicules of four forms, viz. : — 1, skeletal, acuate, smooth, 

 slightly curved, head oval, elongated, Esperia-lifce, constricted, 

 passing on to a fusiform shaft which is wider than the head, 

 ending in an obtuse point, 78 by l-|-6000ths in. in its greatest 

 dimensions (fig. 1, a) ; 2, inequianchorate, in which the free 

 end is small and composed of four teeth that tend towards 

 horizontal rather than vertical extension, shaft long and much 

 curved, fixed end, which is also small, quadrilateral in appear- 

 ance, total length ll-6000ths in. (fig. 1, b,f, g, h) ; 3, biha- 

 mate, simple, the only one seen (in the preparation) and that 

 broken off at one end, which has been supplied in the repre- 

 sentation (fig. 1, c) • 4, minute inequianchorate with elon- 

 gated, spine-like process prolonged from the small end, about 

 4-6000ths in. long (fig. 1, d). No. 1 is plentifully distri- 

 buted throughout the tissue with Nos. 2 and 4 ; the former, 

 that is the large inequianchorate, chiefly en groupe or in the 

 so-called "rosette" form (fig. 1, e). Size of specimen about 

 4 in. high by 5 x 2 in. horizontally in its greatest dimen- 

 sions. 



Hob. Marine, growing over the skeletal fibre of a dead 

 Psammonematous sponge. 



Loc. Port Phillip Heads, South Australia. Depth &c. not 

 given. 



Obs. This species is chiefly characterized by the free end of 

 the large inequianchorate (No. 2) being furnished with four 

 teeth ; by " free " here is meant that end which en groupe, 

 that is, in the globular rosette-form, is outside (fig. 1, e) . The 

 presence of the minute inequianchorate with spine-like end 

 (fig. 1, d), although not peculiar, is uncommon (see ' Annals,' 

 1882, vol. ix. pi. xi. fig. 16, e,f, erroneously written " equi- 

 anchorate" at p. 298). 



Had not Dr. Bowerbank's inequianchorate from an " unde- 

 scribed species of Hymeniacidon from Freemantle, Australia/' 

 which was also "parasitical," been " tridentate " (Mon. Brit. 

 Spong. vol. i. pp. 49 and 249, fig. 135, pi. vi.), I should have 

 identified it with that of Esperia parasitica from its great 

 resemblance ; at the same time I must at least observe that a 

 fr-identate form of inequianchorate could never present its teeth 

 in the position given to them in Dr. Bowerbank's figure ! 



Ann. & Mag. N. Hist. Ser. 5. Vol xv. 9 



