SPONGES. 24 1 



(89.) TOPSENT. " Quelques Spongiaires du Biinc cle Campeche et de la Pointe-a-Pltre." ' M<$m. Soc. Zool. 



de France,' tome 2. 1889. 

 (90.) THURSTON. " Rame'svaram Island and Fauna of the Gulf of Manaar." ' Madras Government 



Museum,' Bulletin No. 3. 1895. 



(91.) TOPSENT. "Eponges de la Mcr Rouge." ' Me'm. Soo. Zool. de France,' tome v. 1892. 

 (92.) TOPSENT. " Note sur quelques Eponges du Golfe de Tadjoura." ' Bull. Soc. Zool. de France,' 



tome xviii. 1893. 



DESCRIPTION OF PLATES. 

 PLATE I. 



Fig. 1. Hmvlella imlica; vertical section of R.N. 46, combined drawing. 



Ch., inhalant chones; Ch.L., choanosomal lamella; Cr., sub-cortical crypts; Ed., ectosome; 



F.C., flagellate chambers; L.E.C., larger exhalant canal; Mem., roofing membrane of 



inhalant chones; P. B.C., primary exhalant canals; P.I.C., primary inhalant canals; 



Sy.A., symbiotic algae. 



2. Hexadella indim ; small portion of vertical section through choanosomal lamella, more highly 



magnified (ZEiss F., Oc. 2). 

 C.T.C., connective-tissue cells; Ep., epithelium lining primary inhalant and exhalant canals; 



I.Ca., inhalant canaliculi. (Other lettering as before.) 

 3. Hexadella indim; tangential section of the ectosome, seen from below, showing the inhalant 



chones, c. x 52. (Lettering as before.) 

 4. PlaJdnastrella intermedia ; R.N. 224. x 2. o., vent. 

 5. Ecioni'ina mrti'i'i ; R.N. 175. x 2. o., vents; p.g,, pore-sieves. 

 ,, 6. TMlla ]wculif?m ; R.N. 230. x 3. Upper part in section. 



Cl., cloaca; L.E.C., larger exhalant canals. 

 ,, 7. Tetilla limicola ; R.N. 70. Nat. size. 



o., vents ; r.t., root tuft of spicules matted together with mud. 

 8. Taprubanr herdmani ; R N. 40. Slightly reduced ; from a photograph. 



PLATE II. 



Fig. 1. Dwdtopsia ceylomca ; R.N. 139. Spicules. All x 230. 



a.-h., calthrops and triods ; i.-o., oxea. 

 ., 2. riakinastrella infmnrtliu ; R.N. 224. Spicules. 



a.-(i., dichotriaenes, x 52 ; r.-n., oxea, x 52 ; <>.-}>., microxea, x 230 ; q.-v., oxyasters, x 230. 

 ,, 3. Plakinaslrella sdmhei ; R.N. 149. Spicules. 



a.-d., triaenes, x52; e.-q., oxea, x52; r.-l., microxea, x230; H.-J:, oxyasters, x 230. 

 4. Pilockroln . liairh'U ; R.N. 127. Spicules. All x 52. 



., orthotrisene ; /., monstrous form of orthotriagne ; <:., anatriasne; </., '., monstrous forms of 



anatriosne. 

 ,, 5. Pilochrota Iwrnclli ; R.N. 176. Spicules. 



., b., orthotriaenes, x 52 ; <., </., cladomcs of orthotri;i;nes seen from alx>ve, x 52 ; p., anatriaene, 



x 52 ; /., oxeote, x 52 ; ;/.-*., chiasters, x 230. 

 6. WclMtii Iti'i-itiiHtni; R.N. 137. Spicules. 



((,.-(., triasnes, x 52 : d., oxeote, x 52 ; c.-li., chiasters, x 230 ; i.-L, oxyasters, x 230. 

 7. M'llr/ta n-xti,ji am : R.N. 200A. Spicules. All x 230. 



a.-il., reduced triasnes ; <., oxeote; /., if., spherasters ; /*., /., nxvasU-rs. 



2 I 



