272 Mr. H. J. Carter on 



To this I would add the illustrated observations of Prof. 

 F. E. Schulze on the development of the species of Ilali- 

 sarca, the faintly of the Chondrosidse, and Corticium cande- 

 labrum respectively (Zeitschrift f. wiss. Zoologie, Bde. xxviii. 

 and xxix. of 1877 and Bd. xxxv. of 1881) ; also Dr. R. v. 

 Lendenfeld's " Preliminary Report on the Australian Myxo- 

 spongise " (Proc. Linn. Soc. N. S. Wales, vol. x. pt. 1, p. 139, 

 pis. i.-v.). 



With reference to my account of ^^ Halisarca australiensis " 

 in the ' Annals' of 1885 (vol. xv. p. 196), Dr. v. Lendenfeld 

 has stated {ih. vol. xvi. p. 21) that " it is not a sponge at all, 

 but the crusts described by Carter under the above name are 

 the ova of Boltemas surrounded by their folliculi ; " which, ah 

 initio^ may be refuted by simply drying a piece of the stem of 

 a Boltenia with a portion of the crust on, when the latter will 

 be found to be homogeneous in structure, like dry glue, and 

 the former heterogeneous (that is, the cartilage of which the 

 stem is composed), more or less charged with the cells, which 

 Dr. Lendenfeld appears to me to have mistaken for " folliculi " 

 of the Boltenia, 



If, now, we go further, and examine a portion of the ovary 

 of the Ascidian itself, it will be found that the ripening of the 

 ova for expulsion takes place successively, so that the whole 

 is not discharged at once in a mass, like the spawn of Gaste- 

 ropods &c., and therefore could not form a " crust " on the 

 Btem of the Boltenia. 



While if sections be made of the " crust " when fresh or 

 undried, it will be found to contain no appearance of ova 

 whatever, but, on the contrary (especially when stained) , will 

 be found to present pores on the surface leading into elon- 

 gated chambers, followed by the ampullaceous sacs (Geissel- 

 kammern) themselves ; thus, independently of the dried con- 

 dition, proving at once that the crust on the stem of Boltenia 

 australiensis is not the spawn of an Ascidian, even if there 

 were such a thing, but a hondjide Halisarcous sponge. 



Having had to repeat my examination of this " crust," 

 together with that of tlie other specimens of Halisarca austra- 

 liensis whose characters were originally included under this 

 heading, it now seems to me that in my description I have 

 mixed up at least three forms, which might be more conve- 

 niently divided into Halisarca australiejisis^ H. ascidiarum^ 

 and H. reticulata, since the solidity of the former, the incrust- 

 ing character of that on the stem of Boltenia australietisisy 

 and the strongly marked reticulated structure of the surface 

 "" of the latter, if not specifically distinct, are so varietally. 



