524 



SCIENCE 



[N. S. Vol. XXXVII. No. 953 



It is quite probable that -well records in 

 western New York will supply additional 

 interglacial records as has been so abundantly 

 done by the well records of Minnesota, Iowa 

 and Ohio. The records in ISTew York state re- 

 ferred to above, whUe few in number, are still 

 of a character to supply indubitable proof of 

 a Prewisconsin ice invasion in this territory. 



During the work of compiling literature re- 

 lating to the life of postglacial and intergla- 

 cial deposits, it was observed that little or no 

 attention had been given by New York geol- 

 ogists to the fresh-water life of the ancient 

 lakes of the Champlain substage. The gravels 

 of the Niagara River* and certain deposits at 

 Ithaca"' appear to be the only localities from 

 which life has been definitely reported. Many 

 years ago Hall" reported Unios and wood from 

 the ridge bordering the south side of Lake 

 Ontario, which marks the shore of the glacial 

 Lake Iroquois. A careful study of this old 

 beach and especially of bays or lagoons be- 

 hind the beach proper will surely produce re- 

 sults similar to those obtained by Professor 

 Coleman at Toronto.' 



Frank Collins Baker 



Chicago Academy of Sciences 



the production in kittens inoculated v7ith 



entamceba tetragena of pathological 



forms identical with entamceba 



histolytica 



To THE Editor of Science: Schaudinn 

 stated that the reproduction of E. histolytica 

 by sporulation "occurs after a period of 

 lively increase when the conditions of life 

 have deteriorated. In dysentery this is simul- 

 taneous with the commencement of healing." 



I have been able recently by the rectal in- 

 oculation of a succession of kittens with 

 trophozoites of E. tetragena to observe during 

 a " period of lively increase " the adolescent 

 trophozoite gradually become reduced in size 

 and to note the production of chromidia in 



^Letson, Bull. Buf. Soc, N. S., VII., pp. 238- 

 252, 1901. 



" Tarr, Journ. of Geol., XII., p. 79. 



•"Geology of New York," Part IV. 



'Bun. Geol. Soc. Amer., XIV., pp. 347-368. 



large amount in every individual. This ap- 

 peared first in the third remove as fine par- 

 ticles in the cytoplasm. In the fourth remove, 

 collections of large particles were seen. The 

 nucleus took on the characters of E. tetragenn, 

 i. e., prominent karyosome, and at the time of 

 death of the last set of kittens in the fourth 

 remove, typical tetragena cysts were seen, but 

 associated with them were forms in which 

 bizarre appearances identical with those fig- 

 ured by Hartmann from Schaudinn's histo- 

 lytica preparations were seen. These are cer- 

 tainly manifestations of pathological cell 

 changes, and represent dislocations of the nu- 

 cleus, karyorrhexis, karyolysis and extrusion 

 of the nucleus. Many so-called buds were 

 seen, a number of which had become detached 

 from the parent body after the extrusion of 

 chromidia. This budding process seems to be 

 analogous to certain pathological changes in 

 the cytoplasm of mononuclear metazoan cells, 

 for example, in lymphocytes and plasma cells. 



The production of budding and other patho- 

 logical forms identical with the descriptions 

 and drawings of E. histolytica, but produced 

 in kittens in a senile precysting race of E. 

 tetragena associated with typical tetragena 

 cysts indicates almost certainly that E. his- 

 tolytica is a spurious species, having been de- 

 scribed by Schaudinn and Craig from senile 

 races of B. tetragena. 



S. T. Darling 



Ancon Hospital 



indoor humidity 



To THE Editor of Science: In view of the 

 present-day discussion of the subject of in- 

 door humidity some experiments recently car- 

 ried out by the writer may be of interest to 

 those who, like himself, have been bothered 

 by the bugbear of the "70 per cent." which 

 seems to be the optimum value according to 

 most authorities. 



Inside the casing of the hot-air furnace, 

 and right on the dome or hottest part of the 

 firebox, was placed a cast-iron pan with bot- 

 tom shaped to fit closely. By a simple auto- 

 matic device connected with the plumbing 

 this was kept full of water, which was found 



