192 Dr. J. E. Gray on the Oroiotli o/Hyalonema. 



A gular pouch is mentioned by Bertliold and Dr. Hallowell. 

 Like that of N. auratus : the gular pouch is evidently possessed 

 by the male Norojys only. 



The hind limbs are much shorter than in the preceding. 

 The fourth toe is much longer than the third. The under 

 surface of the toes is covered with transverse scales, which, 

 however, are much narrower than the same scales or plates in 

 auratus J as there is no appearance of dilatation in any of the 

 toes. 



The fore limbs, when stretched forward, reach to the extre- 

 mity of the snout, the hind limbs only to the ear-opening. 



The tail is thrice the length of the body. 



Colours as stated above, — well described by Dr. Hallowell. 



Localities given by different writers : — Surinam (Berthold), 

 New Granada (Hallowell), New Granada? (Cope). 



A specimen collected by Mr. Bates at Santarem, Amazons. 



As both Dr. Hallowell and Dr. Peters agree in giv^ing 

 Mexico as the habitat of the iV". auratus^ the latter speaking 

 of six specimens collected by Dr. Hille at Huanisco, it is not 

 improbable that N. auratus is a truly Mexican species, while 

 12-striatus is its South-American representative. 



XXVII. — On the Manner of Growth o/" Hyalonema. 

 By Dr. J. E. Geay, F.R.S., V.P.Z.S., &c. 



The writers of anonymous papers in two scientific journals 

 state that I have adopted Prof. Loven's opinion that the ifi/a- 

 lonema grows rooted in the mud. I thought that by my paper 

 I had sufficiently shown the difference between Prof. Loven's 

 and ray theory. From the examination of the direction of the 

 polypes and the form of the sponge of the specimens which 

 had come into my possession, and the study of Dr. Max 

 Schidtze's description of the sponge of one of his specimens, I 

 was convinced that the sponge to which the Hyalonema was 

 attached could not be attached to any marine body by what 

 Prof. Brandt, Prof. Max Schultze, and I have called its base, 

 and that it must have lived with the so-called base upwards ; 

 and I believed that it did live free, with the free ends of the 

 siliceous filaments sunk in the sand or mud. 



Prof.Lov^n, on the other hand, believes that all the specimens 

 we have in nniseums are imperfect, and have been torn by 

 force from a part of the specimen which is furnished with an 

 expanded root and attached to some marine bodies. 



Dr. William Carpenter does not appear to have a very clear 

 idea of Dr. Loven's ])aper ; for in his very interesting " Preli- 

 minary Beport of Dredging-Operations in the Seas north of 



