ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
45 
they have a remarkable capacity for vacuolation. The protomicrosomes 
are less strongly chromatophilous than the macrosomes, but their affinities 
are distinctively for basic dyes. The structural constituents of the ma- 
cronucleus are free from inorganic iron, but iron maybe unmasked in the 
nucleus by appropriate treatment with acid. The variation which has 
been observed in nuclear structure may be correlated in part with the 
condition of nutrition of Carchesium ; thus specimens nourished on in- 
termittent bacterial diet have scattered macrosomes of medium size ; 
with abundant artificial nourishment the macrosomes increase in size. 
The association of nuclear change with varying nutrition is more than 
coincidental, as may be seen, not only by experimental results repeatedly 
obtained, but by examination of senile or moribund nuclei on the one 
hand, and of the macrosomes during reproduction on the other. 
Miss Greenwood looks forward to the results of histological work 
which shall correspond to and complement the suggestive experiments of 
Yerworn — to study of structural change bound up with those demands 
on nuclear activity which he has associated with the reconstitution of 
divided cells. 
Protozoa of Lake Michigan.* — Mr. C. A. Kofoid has a report upon 
the Protozoa observed in Lake Michigan and the neighbouring inland 
lakes during the summer of 1895. The present paper makes no pre- 
tensions to completeness, being merely a compilation from the daily 
record of work ; it gives the distribution and relative abundance of such 
species as were identified during the six weeks the author studied at 
the laboratory. The list records 81 forms, this number being made 
up of 76 species and 5 varieties. They were thus distributed among 
the different groups : — Kliizopoda 22, Heliozoa 5, Mastigophora 20, 
and Infusoria 34. 
Hygienic Importance of Parasitic Vorticellse.! — Herr G. Lindner 
makes a new communication relative to Vorticella ascoidea. It appears 
that he has succeeded in transferring stalked to unstalked Vorticellse, 
and observed their further development. In the unstalked Vorticellse the 
author sees the direct or indirect cause of disease to animal organisms, 
and several cases are enumerated. Among these was a malady of ty- 
phoid type affecting two labourers, in whose stools Vorticellse were 
found. The author has found Vorticellse in the blood of dogs which 
had been fed with Vorticella. He is of opinion that Miescher’s tubes 
are Vorticella cysts. In eczema of the scalp (from which he suffers 
himself ), the author has found Vorticellse. The cause of muscle poison- 
ing is also assigned to Vorticellse , which convert the albumen into tox- 
albumen. From sarcoma, carcinoma, and cowpox-lymph the author has 
bred cercomonads, but failed to reproduce them from their encysted 
stage. 
ew Amoeboid Rhizopod.* — Herren E. v. Leyden and F. Schaudinn 
have found in the ascitic fluid of living men an amoeboid Rhizopod, 
* Bull. Michigan Fish Coram., No. 6, Appendix ii. pp. 76-84. 
t Deutsche Medizinal-Zeitung, 1896, No. 65. See Centralbl. f. Bakteriol. u. 
Parasitenk., l te Abt., xx. (1896) pp. 705-6. 
x Situngsber. Konigl. Preuss. Akad. d. Wiss. zu Berlin, xxxix. (1896) p. 13 (1 ph). 
See Centralbl. f. Bakteriol. u. Parasitenk., l te Abt., xx. (1896) pp. 465-6. 
