NOTES AND MEMORANDA. 



On the SmaUpox of Sheep.— Klein {' Proc. Eoy. Soc.,' 1874, 

 No. 153) describes the development of the primary pock at 

 the point of inoculation in this disease, which closely re- 

 sembles human smallpox; the fresh lymph used for inocula- 

 tion contains very minute spheroidal micrococci and other 

 forms not previously described, but closely related to micro- 

 cocci. He notes three stages in its development — 1. A pro- 

 gressive thickening of the integument over a rapidly in- 

 creasing but vi^ell- defined area. 2. The formation of vesicular 

 cavities containing clear liquid in the rete Malpighii ; and 3, 

 the filling of these cavities with pus-corpuscles and other 

 structures. About the third day after the pock has ap- 

 peared, there appear in the granular material, which now 

 distends the lymphatics, spheroidal or ovoid micrococci, and 

 branched filaments, either sparse or closely fitted together. 

 This vegetation, after one or two days, presents the character 

 of a mycelium, from which moniliform terminal filaments 

 spring, each of which breaks off at its free end into conidia. 

 The vesicles coalesce into irregular sinuses, and contain 

 similar masses of vegetation, the filaments of which, how- 

 ever, are of such extreme tenuity, and the conidia so small 

 and numerous, that the whole possesses the characters of 

 zoogloea rather than of mycelium. The rete Malpighii be- 

 comes filled with migratory cells which originate in the 

 corium ; these soon find their way to the cavities formed by 

 the coalesced vesicles, which are thus converted into micro- 

 scopical collections of pus-corpuscles. 



The Peach-coloured Bacterium ('Quart. Journ. Micr. Sc.,' 

 1873, p. 408). — Professor Ferdinand Cohn, of Breslau, writes, 

 under date August 8th, to Mr. Ray Lankester: 



" Your Bacterium rubescens is the same thing which 

 Ehrenberg described (but did not figure) in his great work 

 under the name 3Ionas Okeni. The zoogloea-like form was 

 called by Kiitzing Protococcus roseo-persicinus , but was pub- 

 lished by myself last year in Rabenhorst's collections ' Cen- 



