252 PROGRESS OF MICROSCOPICAL SCIENCE. 
after inoculation, infiltrating this tissue, are oval or round nucleated 
cclls, deeply tinged by carmine. d. On successive days, these cor- 
puscles are to be seen in the crypts or hair-follicles budding or 
throwing off minute, round, highly refractive bodies. e. During the 
later stages, when the pock has nearly matured, these corpuscles 
elongate into fibres, or shrink up. jf. In becoming fibres, they 
encroach on the hair-shafts and hair-follicles. In none of the pre- 
parations examined by us have we observed any bacteria, fungoid 
forms, or allied organisms. 
Dr. Klein’s Observation on Small-pox.—We regret that this has 
not been noticed earlier, but it is of so much importance that we 
cannot allow it to remain absolutely nnnoticed. It is this. Dr. Klein 
has been convinced by Dr. Charles Creighton that his observations 
published in the ‘ Philosophical Transactions’ (vol. 165, part 1) are 
in part incorrect. He there described certain structures in the 
lymphatics of the skin as the mycelium of a fungus which he termed 
Oidium variole. He has, since Dr. Creighton published his paper, re- 
called his former observations. With an honesty of purpose for which 
it is hard to praise him too much, Dr. Klein says:—“ A comparison 
of the two kinds of specimens convinced me that the appearances re- 
presented in my figs. 18 and 19 are not due, as I supposed, to a 
mycelium in the cavities of the primary pustules, but are products of 
coagulation of some albuminous or kindred material by the reagent 
that had been employed for hardening the object in question (dilute 
chromic acid and spirit). The vegetable nature of the other structures 
—viz. those represented in figs. 9, 10, and 11 (i.e. the supposed 
mycelium in the lymphatics of the skin of the pock), as well as those 
in figs. 16 and 17 (i. e. the mycelium in the cavities of the secondary 
pustules)—becomes therefore very doubtful. My doubt as to these 
being also produced by coagulation is based partly on the similarity 
between the last-named features and those undoubtedly non-vegetable 
objects in Dr. Creighton’s specimens and also in my figs. 18 and 19, 
and partly on the following circumstances :—(1) I have lately ascer- 
tained that blood, especially in febrile conditions, which is contained 
in blood-vessels of tissues that had been subjected, in a fresh con- 
dition, to the hardening fluid (e. g.c hromic acid), presents appearances 
very similar to branched mycei:ium-threads to which are attached 
numerous conidia; the presence of more or less unaltered blood- 
corpuscles proves their true character. (2) I have likewise seen that 
blood-plasma containing globulin or parts of blood-corpuscles, when 
in lymphatic vessels or kindred spaces, show sometimes in the course 
of coagulation similar appearances. Whether the greater number of 
the thread-like structures is due to fibrin or to blood-corpuscles I 
cannot determine as yet; but it seems to me that both is the case.” 
Mr. Sorby on the Red Clays of the Ocean-bottom.—The President of 
the Royal Society, in his late address, makes the following observa- 
tions on this subject :—‘“ Before leaving this subject, I must mention 
the endeavour of our Fellow, Mr. Sorby, to determine the nature of 
the Red Clays of the ocean-bottom, of which we have heard so much. 
