LITEEATUKE. 297 



N. B. — To uiy regret I have inadvertently failed to get access to the two following 

 works : 



W. Maeshall. Spongiologische Beiträge. Festschr. z. 70sten Wiederkehr d. Geburtst. 

 V. E. Leuckart. Leipzig, 1892. 



C. Gravier. Sur une collection d'épongés (Hexactinellides) du Japon. Bull. Mus. 

 d'hist. nat. Paris. T. V, no. 8, pp. 419-é22. 



The former paper, as known to me through an abstract, should touch upon matters which 

 demand attention in relation to the morpliology and physiology of the Hexactinellida. The 

 latter paper may possibly contain notes on some of the species described in this Contribution. 

 I beg indulgence for any omissions in reference to these works. — I also very much regret 

 that I have not been able to benefit by Minchin's ' The Porifera ' (in Lankester's Treatise 

 on Zoology), the ajjpearance of which work has become known to me too late to admit of 

 my securing a copy of it before finishing the printing of this Contribution. 



