1867.] Zoology and Animal Physiology. 445 



Pterylography is not a subject which has been much taken up 

 in England ; indeed the papers by Dr. Sclater and Mr. Bartlet 

 appended to this volume are amongst the only contributions to its 

 development in this country ; hence Mr. Dallas's translation will 

 be found acceptable by all scientific ornithologists, and ought to 

 bear good fruit. 



The Glass-rope. — The veteran zoologist Ehrenberg has com- 

 municated a paper on this much-discussed organism to the Berlin 

 Academy. He, it appears, formerly considered the Hyalonema to 

 be simply an artificial product of Japanese industry. He now aban- 

 dons that notion, and gives his reasons for regarding it as a Sponge. 

 At the same time he urges in a most curious way the vegetable nature 

 of sponges, and regards the long hair- like spicules of the glass-rope 

 as tending to confirm his view of the vegetable nature of sponges in 

 general. He adduces the fact of the inhalent orifices of sponges 

 being permanently open, as evidence against their animal nature, 

 for no animals have a permanently open mouth; thus he attributes to 

 zoologists who do not agree with him the view that a sponge is not 

 a complex mass of units, but rather a few individuals conjoined 

 whose mouths and anal apertures are respectively represented by 

 the inhalent and exhalent orifices. Good evidence appears to have 

 been brought forward in favour of the existence of a European 

 species of Hyalonema ; but this part of the question is certainly not 

 yet definitely settled. 



Excavating Sponges. — Mr. Albany Hancock, who in 1849 pub- 

 lished a paper on these curious perforating organisms, has lately 

 returned to the subject. He fully admits that at present the question 

 as to the manner in which they excavate shells is not solved, their 

 power being obtained perhaps by means of their spicula or by some 

 other method. Dr. Bowerbank, in his Monograph of the British 

 Spongiadae, maintains that the minute galleries in the shells in which 

 these sponges occur are excavated by " lithodonious Annelids." 

 Mr. Hancock remarks that if this is so, we ought to find the annelid 

 there, which we do not ; only one annelid is recognized as perfo- 

 rating limestone, in the manner which Mr. Hancock attributes 

 to Cliona, and that is a species of Leucodore. Mr. Hancock shows 

 also very clearly that the dendritic and irregular character of the 

 Cliona borings differs from anything similar done by worms. He 

 describes four new species, characterized by the form of their spicula. 

 They occur in the shell of a species of Chama ; in the shell of a Pur- 

 para, from Mazatlan ; in the shell of Spondylus goederopus, from 

 the Mediterranean ; and in the shell of a Serpula, adhering to a 

 Chama from Mazatlan. 



