">."> 1 Presents. [May 28 r 



Ichthyopsidan types. The most that can be said at present, with any- 

 thing like certainty, is that the Dipnoi are the isolated survivors of 

 an exceedingly ancient group, which was probably related to the 

 ancestors of existing Fishes and Amphibians. Amongst the former, 

 the connexion seems to be closest to the Elasmobranchs, more par- 

 ticularly to the Chimseroids on the one hand, and to such an ancient 

 Selachian type as Chlamydoselache on the other; but at the same 

 time, the Ganoids probably arose from the common ancestral stock 

 not very far off. Though retaining many primitive characters, the 

 Dipnoi, and more especially Protopterus and Lepidosiren, are in some 

 respects highly specialised, the specialisation being largely due to a 

 change of habit. 



V. " On the Constitution of the Terpenes, Camphors, and 

 Camphor Acids." By J. NORMAN COLLIE, M.D. Communi- 

 cated by Professor RAMSAY, F.R.S. Received April 29, 

 1891. 



[Publication deferred.] 



Presents, May 28, 1891. 

 Transactions. 



Acireale : Societa Italiana dei Microscopisti. Bollettino. Vol. I. 

 Fasc. 4. 8vo. Acireale 1891. The Society. 



Baltimore : Johns Hopkins University. Studies in Historical 

 and Political Science. Nos. 5-6. 8vo. Baltimore 1891 ; 

 Annual Report, 1890. 8vo. Baltimore. With Twelve Dis- 

 sertations and Excerpts. 8vo. The University. 



Berlin : Gesellschaft fur Erdkunde. Zeitschrift. Bd. XXVI. 

 No. 2. 8vo. Berlin 1891. The Society. 



Bnda - Pest : K. Ungarische Geologische Anstalt. Foldtani 

 Kozlony. Kotet XXI. Fiizet 1-3. 8vo. Budapest 1891 ; 

 Jahresbericht fur 1889. 8vo. Budapest 1891 ; Mittheilungen. 

 Bd. IX. Heft 3-5. 8vo. Budapest 1891. The Institute. 



Calcutta : Asiatic Society of Bengal. Proceedings. No. 1. 8vo. 

 Calcutta 1891 ; Annual Address to the Asiatic Society of 

 Bengal. 8vo. Calcutta 1891. The Society. 



Cambridge, Mass. : Museum of Comparative Zoology, Harvard 

 College. Bulletin. Vol. XXI. No. 1. 8vo. Cambridge 

 1891. The Museum, 



Chapel Hill, N.C. : Elisha Mitchell Scientific Society. Journal. 

 Vol. VII. Part 2. 8vo. Raleigh 1891. The Society. 



