1 88 1.] Microscopy. 345 



by a quite distinct view of the surface of the corpuscle covered 

 with small nodules of unequal size and placed at irregular inter- 

 vals, clearly denned, and capable of casting shadows in various 

 directions. No net-work could be seen between or below these 

 nodules, though in some cases their shadows might seem to 

 resemble one. Aside from the opinion of so competent a judge 

 of appearance as Dr. Curtis, it may be added that the appearance 

 of nodules in the absence of a net-work, as figured in the draw- 

 ings representing his observations, indicates clearness of definition 

 and reality of structure as distinguished from optical illusion. 

 The only real question is whether a net-work of fibers, on another 

 plane underlying this could have escaped detection by the same 

 means which rendered the nodules so distinct. While the 

 nay not be considered absolutely conclusive 

 question, contested by so competent authority, 

 still it is a valuable and interesting contribution to the subject, 

 and it is quite sufficient to teach caution in adopting a theory 

 which may yet be discarded along with the hexagonal markings 

 of r/atrosig-jua angitlatum. 



An interesting paper by C. M. Vorce, of Cleveland, on " Forms 

 observed in water of Lake Erie," discusses the various vegetable 

 and animal organisms obtained by filtration, through a muslin 

 bag tied over a faucet, from the water supply of the city of Cleve- 

 land. Besides casual observations made at other times, regular 

 weekly examinations were made for a year or more. Nearly 200 

 forms are figured upon a folded plate. The following general 

 conclusions are of special interest : " Surprising to the writer 

 was the discovery that the winter season was the most prolific of 

 the whole year in number and variety of forms observed. * * * 

 The most noticeable peculiarity of the filterings taken at this 

 season is the abundance of infusoria, rotatoria and Crustacea, 

 which in small bodies of water are warm-weather forms ; and 

 next in attracting attention is the remarkable activity of repro- 

 duction in vegetable life. Indeed, it is soon apparent to the ob- 

 server that while the advent of wintry frosts almost suspends the 

 course of growth and reproduction in most allied forms in small 

 and shallow waters, in these vast watery worlds the course of life 

 with these minute organisms goes unceasingly on without a rest, and 

 with, indeed, no perceptible check or stay. When the change in 

 volume is imperceptible, ami the change in average temperature 

 but a few degrees, there is for the forms in these great waters lit- 

 tle or no need for nature to resort to ' winter eggs ' and ' resting 

 spores,' although they are sometimes found, more, probably, from 

 organic idiosyncracy than from climatic or local causes, such as 

 chiefly contribute to cause such life changes in usual circum- 

 stances. In the lake waters the advent of spring exhibits no 

 other effect upon the organisms we are considering than to cause 

 an acceleration of the processes of multiplication and reproduc- 



