148 [June 19, 



having simple fistulo-fibrous skeletons ; it contains one genus, 

 Verongia. The fifth suborder contains sponges which have com- 

 pound fistulo-fibrous skeletons, and is represented by the genus 

 Auleskia. The sixth suborder consists of sponges having regular 

 semi-areno-fibrous skeletons, and is represented by the genus Stema- 

 tumenia. The seventh suborder has irregular and entirely areno- 

 fibrous skeletons ; it is represented by the genus Dysidea. The 

 whole of these genera (those previously established as well as the new 

 ones proposed by the author) have been characterized in accordance 

 with their anatomical structures. 



The author concludes his paper with a dissertation on the discri- 

 mination of species, and a general review of those portions of the 

 organization that may be applied with advantage to their scientific 

 description. The principal sources for this purpose being 1st. 

 The spicula. 2nd. The oscula. 3rd. The pores. 4th. The dermal 

 membrane. 5th. The skeleton. 6th. The interstitial membranes. 

 7th. The intermarginal cavities. 8th. The interstitial canals and 

 cavities. 9th. The cloacal cavities. 10th. The sarcode ; and llth. 

 The ovaria and gemmules. And, finally, directions for the examina- 

 tion and preservation are given, with a few examples of the mode of 

 specific description proposed by the author. 



VI. " On the Spectrum of Carbon." By JOHN ATTFIELD, Esq., 

 F.C.S., Demonstrator of Chemistry at St. Bartholomew's 

 Hospital. Communicated by Dr. FRANKLAND. Received 

 June 19, 1862. 



(Abstract.) 



The author has prismatically examined various flames containing 

 carbon. He finds that certain rays of light are common to ignited 

 oxycarbons, hydrocarbons, nitrocarbons, and sulphocarboris, and 

 concludes that these common rays are those emanating from ignited 

 carbon vapour. By special manipulation he obtains the carbon 

 spectrum with olefiant gas, cyanogen, carbonic oxide, and bisulphide 

 of carbon. Observed by the naked eye, the prevailing colour of 

 ignited carbon is light blue. 



