C. Porifera calcaria. 9 



of descent, but along several . Subdermal spicules are defined as lying 

 beneath the dermal surface and with inwardly directed basal or apical rays as 

 the case may be. An abstract of the author's classification is given below in 

 synoptical form. 



A. No dermal membrane outside the inhalant canals . . . Order II. Sycettidae. 



B. Dermal membrane present 



1 . Long, branched , flagellated chambers , with ex- 

 halant canals, skeleton irregular, no subdermal 



radiates I. Leucascidae. 



2. Canal system various, skeleton regular or irregular 



a) no subdermal radiates III. Grantidae. 



b) subdermal triradiates IV. Heteropidae. 



c) subdermal quadriradiates V. Amphoriscidae. 



Order I. Leucascidae includes only Leucascm n. (2 new species). II. Sycet- 

 tidae (a) chambers not intercommunicating: Sycetta (no tufts of oxea on the 

 chamber-ends) and Sycon (with such tufts) ; (b) groups of chambers intercommuni- 

 cating by openings in their walls: Sycantha fide Lendenfeld. III. Grantidae. (a) 

 elongated radial flagellate chambers 1 . tubar skeleton articulate, except in Vie, 

 where it may consist of the basal rays of subgastral triradiates : Grantia (no 

 longitudinal oxea in cortex, no tufts of oxea on chamber-ends. Subgenus Gran- 

 tiopsis, well marked cortical layer of inhalant canals) ; Ute (large longitudinal oxea 

 in cortex. Subgenus Synute, compound form); Utella (gastral layer of oxea). 

 2. no special tubar skeleton : Anamixilla. 3. Sycyssa huxleyi fide Haeckel (oxeote 

 spicules only), (b) flagellate chambers spherical or sac-shaped or unknown : Leu- 

 candra (skeleton irregular) , Lelapia fide Gray & Carter ( tuning - fork - shaped 

 triradiates, large longitudinal oxea); Leucyssa fide Haeckel (oxeote only). IV. He- 

 teropidae. (a) elongated radial chambers: Grantessa (no longitudinal oxea in 

 cortex); Heteropia (large long, oxea in cortex), (b) spherical or sac-shaped cham- 

 bers: Vosmaeropsis n. gen. (no long oxea in cortex). V. Amphoriscidae (a) 

 elongated radial chambers ; Heteropegma ( vestigial tubar skeleton ) ; Amphoris- 

 cus (chamber larger, supported only by apical rays of subdermal and subgastral 

 quadriradiates) ; Syculmis synapta fide Haeckel (like Amph., but with anchoring 

 tuft) (b) spherical or sac-shaped chambers: Leucilla and Paraleucilla. Details 

 of the Australian species are given. Colour: a Leucandra microraphis green in 

 life, probably due to symbiotic algae ; a specimen of Vosmaeropsis wilsoni violet 

 purple. Size: Grantia labyrinthica five inches across the top. Gastral cavity: 

 in a specimen of Ute spenceri partly bounded by the back of a crab on which it 

 grew, [G. P. Bidder] 



Doderlein gives to an organism from the bay of Sagami in Japan, probably 

 100 fathoms, the name of Petrostoma schuhei; placing it in a new group of Cal- 

 carea, the Li th ones. Only dried examples were obtained. It closely resembles 

 in appearance and consistence Millepora tenella, a specimen of some 20 anastomos- 

 ing branches measured 5 cm in breadth by 3,5 cm in height. The microscope 

 shows that the outer surface is full of the well-known slender triradiates and 

 quadriradiates of Calcareous Sponges , between which can be seen numbers of 

 the surface pores, so characteristic for the outer covering of sponges . Among 

 the quadriradiates are some with thick irregular arms , by the fusion of which 

 the solid inner skeleton is formed, taking the form of a strong radial framework, 

 between them are smaller spicules roughened with knots and spines. Three 

 rays of each quadriradiate turn toward the axis of the branch and one is centri- 

 fugal [they therefore correspond to the subgastral quadriradiates of Syconidae], 

 the outer covering layer stretches from point to point of the centrifugal rays. In 



