1 882.] Proceedings of Scientific Societies. 437 



— A third edition of Quenstedt's Handbuch der Petrefakten- 

 kunde is now being issued in numbers. The first lieferung be- 



— The Transactions of the American Fish Cultural Associa- 

 tion, tenth annual meeting, comes to us, containing some excel- 

 lent matter. 



PROCEEDINGS OF SCIENTIFIC SOCIETIES. 



Philadelphia Academy of Sciences. Oct. 11, i8Si.— Dr. H. 

 C. Wood, in the course of a lecture on diphtheria detailed various 

 experiments and observations made by himself and Dr. H. For- 

 mad with a view to ascertain the cause of that disease. Inocula- 

 tion under the skin of some of the lower animals with diphtheritic 

 poison failed to produce the disease, but inoculation by the wind- 

 pipe caused death with diphtheritic symptoms. Other irritants 

 similarly introduced produced false membrane. 



Samples of diphtheritic poison were then obtained from Lud- 

 dington, on Lake Michigan, where diphtheria of the most virulent 

 type raged, chiefly in the third ward, which was built upon a swamp 

 filled up with sawdust. Micrococci swarmed in the blood of the 

 children suffering from the disease at this place, and this diphther- 

 itic matter produced all the symptoms of malignant diphtheria, at- 

 tended with swarms of micrococci in the blood, in animals inocu- 

 lated with it. These micrococci existed in the white blood 

 corpuscles to the number of forty or fiftv in each, causing the dis- 

 integration of the corpuscle. They abounded also in the spleen 

 and bone marrow. In suitable liquids infected with the diphther- 

 ic matter from Luddington, it was found that generation after 

 generation of micrococci could be produced indefinitely, whereas 

 die matter from the milder type of the disease prevailing in 

 Pndadelphia, exhausted its productive power in three or four 

 generations. Micrococci are present in healthy throats, but lack 

 this power of continued development. Micrococci obtained on 

 niter paper from the watery discharges of malignant cases proved 

 more fatal when planted 'in animals thin the membrane itself. 

 Micrococci grown in liquids re .n> 1 i- ed diphtheria when intro- 

 duced into animals. The inference to be drawn was that the 

 micrococci were the active agents in producing the disease, while 

 neir existence m healthy persons was explained by the supposi- 

 tion that, as is known to be the ease with some fungi, the same 



' " ' ' ' -■ ": '' ". ■ , ' ■■.■•■ - - « 



with the cultivated poison of cxanthematous diseases might even- 

 u ally be practiced as a protection against severer attacks. 



Oct. 18.— M r . Meehan called attention to two forms of willow 

 ^aves from the same tree, one form an inch in width, the other 

 not more than a line, and argued that this tended to show the pro- 

 ton of variations by sudden leaps. 



