INVERTEBRATA, CRYPTOGAMIA^MICROSCOPY^ ETC. 275 



Diamond Island off the coast of Pegu ; Halicornaria setosa, off Cape 

 Negrais in 80 fatlioms, Cheduba Island in 8 to 10 fathoms ; Hali- 

 cornaria plamosa, off Capo Comorin in 35 to 40 fathoms, and off 

 Cheduba Island in 10 to 15 fathoms ; Himaria compressa, in abund- 

 ance off Diamond Island and on the Konkan coast, also off Cape 

 Comorin ; Anlennella Alhnanni, off Cape Comorin in 50 fathoms, and off 

 Cheduba Island in 8 to 10 fathoms ; Sertularella rigosa, off Cape 

 Comorin in 40 fathoms, and off the Arakan coast in from 10 to 15 

 fathoms ; Desmoscyphus humilis, on the coast of St. George's Island, 

 West Coast of India ; Endendriiim ramosum, oft' Cape Comorin in 40 

 fathoms, and very sparingly along the coast of Arakan in from 10 to 

 70 fathoms. 



With the exception of a single species, all the above hydroids are 

 calyptoblastic. The one exception is Endendrium ramosum, which is 

 a typical gymnoblastic zoophyte, and is especially remarkable in 

 having the gonophores borne, not upon a true blastostyle, but upon 

 atrophied hydranths from which the tentacles have disappeared. 



Species of Hydra. — Dr. W. Haacke * promises a treatise upon this 

 genus, which is to show that only two species are to be distinguished 

 with certainty which are not green. In the first of these, to be 

 named H. Tremhleiji, the bud jiroduces all its tentacles at one time ; 

 in the second, H. Boeselii, but two, oj^posite, tentacles appear at first, 

 the rest appear singly. Some particulars of special interest in the 

 development of the tentacles in H. Boeselii are also to apjDcar. 



Porifera. 



Structure of Siliceous Sponges-t — In the eighth of his contribu- 

 tions to the structure and development of sponges, Professor F. E. 

 Schulze gives an account of Nardo's Hircinia, and of his own new 

 geniis Oligoceras. Under the single genus Hircinia he includes, be- 

 sides the forms usually grouped under that name, Stemaiamenia, Filifera, 

 Sarcotragus, and Pohjtherses. 



1. Hircinia variabilis. — Under this designation Schulze includes 

 the six species of Oscar Schmidt's subgenus Hircinia, notwithstanding 

 the great diftcrences they exhibit in external form, colour, arrangement 

 of spicules, &c. The oscula may be flush with the surface or sur 

 rounded with a raised rim ; they may or may not bo provided with a 

 sphincter. 



The pores are sometimes connected with straight canals leading 

 into the interior of the sponge ; at other times these canals anastomose 

 by cross branches, which may be dilated into large subdermal cavities. 

 The thickness of the cortical layer above these cavities varies greatly 

 even in the same siiongc. Tlio canals leading from the subdermal 

 cavities to the ciliated chambers are irregularly branched and pre- 

 sent transverse or obli(iuo constrictions at frequent intervals. Their 

 terminal branches communicate by small round pores with the hemi- 

 spherical ciliated chambers, each of which may possess more thiiu one 

 poro. From each cliamber proceeds a short funnel-like duct, which 



• ' Zool. AnzciKor,' ii. (187^)) p. iVl'L 



t ' Zeitsch. wisri. Zool.,' .\xiiii. (187'J) p. 1. 



T 2 



