16 JVIr. H. J. Carter on the Suhspherous Sponges. 



1st of August. Dr. Bowerbank announced his description of 

 those apertures at the meeting of the British Association held 

 on the 30th of August ; and on the 1st of September appeared 

 the other part of my paper, to which my note on the subject 

 was appended. Thus, had the whole of my paper been pub- 

 lished at once, I should have preceded Dr. Bowerbank in his 

 announcement by just one month. Yet Dr. Bowerbank very 

 frequently alludes to his own announcement both in the ' Philo- 

 sophical Transactions ' and in the ' British Sponges,' of 1862 

 and 1866 respectively, without ever mentioning my name in 

 connexion with it ; while my figure and particular account of 

 those apertures, in the ' Annals ' of 1857, is still, I believe, the 

 only published illustration of the fact. 



If it be assumed that this reticence arose from not reading 

 my papers, then it must be also assumed that Dr. Bowerbank 

 did not read what was published on his own special subject, 

 and, consequently, that what is stated in the ' British Sponges' 

 &c. is mostly upon his own iptse dixit : lacking, therefore, 

 authority, it lacks confidence. 



It matters little who has discovered these apertures, so long 

 as the fact is made known to the public ; but the suum cuique 

 should be a sacred obligation among individuals ; and nothing 

 that is put before the public loses by additional evidence. 



Olohular crystalloids. 



This term I use for the little siliceous bodies which, closely 

 packed together, form a hard crust on Geodia and Pachyma- 

 tisma, whether free or in contact with attached pieces of rock 

 or coral, and also sometimes coat the calibre of the larger ex- 

 cretory canals of the latter for some distance into the paren- 

 chyma of the sponge ; so that they are evidently accumulated 

 in those parts which are most likely to come into contact with 

 foreign objects. They are imbedded in living sarcode of the 

 sponge, which, acting as a plastic bond of union between them, 

 thus gains access to the surface, where it forms the dermoid 

 layer, charged, as before stated, with minute spicules peculiar 

 to the species. 



They are found generally in a more matured form in the 

 crust, especially in Pachymatisma, than in the body of the 

 sponge, and, after full development, might be transferred from 

 the latter to the former probably as easily and as naturally as 

 an Amoeba discharges its undigested material through the 

 surface of its body, viz. without injury. But being chiefly 

 confined to the crust in Geodia arabica, Avhile they abound 

 generally in the body of Pachymatisma Johnstonia, it becomes 



