BY DR. R. VON LENDENFELP. 131 



In 1860, Max Schultze (46) published a paper on Hyalonrma, 

 which at that time, when deep sea dredging was unknown, 

 was very rare, and described it as the skeleton of a sponge 

 affixed to the bottom of the sea by the long glassy threads which 

 grow out from one extremity of it. 



By many nativralists the Hyalonemas were considered as 

 artificial products, made by the Japanese out of glass. Ehrenberg 

 (47) held that opinion amongst others, and attempted to prove 

 the inefficiency of Schultze's paper. In the subsequent contro- 

 versy the animal nature of these Hexactinellid sponges was proved, 

 although Ehrenberg himself never acknowledged that he had 

 made a mistake. 



With the year 1862 we enter into the modern and most 

 fruitful period of the study of sponges, and we can safely say that 

 everything published before that year, since Aristoteles, is not of 

 such value as the discoveries made in every one of the years, from 

 1862 to 1884. 



Bowerbank (48) publishes a series of valuable observations on 

 the Anatomy of the sponges, and dwells in detail on the spicules, 

 which are accurately figured and described. 



Lieberkiihn (49) continues his observations on Spongilla ; among 

 the important results of his investigations, I will mention the fact, 

 that he thinks he has observed, that the ciliated Embryos of 

 Spongilla sometimes multiply by fission, a statement of great 

 importance. 



Kolliker gives a preliminary notice of his histological investiga- 

 tions, in the same year. A full account of this most important 



(46) Max Schultze. Die Hyalonemen, ein Beitrag zur Kcdurgeschichte 

 der Spongien. Bonn., 1S60. 



(47-) (J. Ehrenberg Bertrage zur Beuriheilung der Gattung Hyalonema. 

 Monatsberichte der Akadem. Berlin I860, p. 173. 



(48). T. J. Bowerbank. On the Anatomy and Physiology of the Spongiadce. 

 Phil. Trans. Roy. Soc. Vol. 148, p. 279. Vol. 152, p. 830. Vol. 152, p. 

 747- A r ol. 152, p. 1082. 



(49). N. Lieberkiihn. Ueber Beicegungserscheinungenbei den Schvximmen. 

 Midlers Archiv., 1863. Seite, 717. 



