1882.] 



MICKOSCOPICAL JOURNAL. 



151 



mentioned, as far as I know, in con- 

 nection with the cyclosis. This weed 

 grows 6 to 12 inches in length, has 

 flat, narrow leaves, somewhat crowd- 

 ed into whorls. It is called by botan- 

 ists the Natas flexilis, and classed 

 by Dr. Gray,* in the family Naiadacese 

 genus Naias. This Naias flexilis dis- 

 closes, under my microscope, the 

 finest cyclosis phenomenon I have 

 ever seen. I have mentioned this fact 

 to a distinguished botanist, and to 

 several eminent professors and micro- 

 scopists, each of whom was unaware 

 of its revealment of the clyclosis, and 

 I therefore infer that others may be 

 interested in this discovery. 



On the outer side of the wooden 

 pier, near the hotel, at Fresh Pond, 

 there is a depth of ten or twelve feet 

 of water, with a healthy growth of 

 Anacharis alsinastruvi on the bottom. 

 On the left-hand, the water is eight 

 or ten feet deep, and the bottom is 

 literally covered with a fresh matting 

 of Naias flexilis. 



In a drop of water, place a small 

 portion of the leaf of this plant on a 

 microscope slide, v.dth a thin glass 

 cover — or better, use an animalcule 

 cage. Let it remain quiet a few min- 

 utes, then view it with a mediuum 

 eye-piece and a -^-inch objective or ' 

 higher power. 



The bioplasm, and the chlorophyll 

 or colored granules, will exhibit the 

 cyclosis most beautifully, better it is 

 believed, than has hitherto been ob- 

 observed in any other plant. 



The Naias flexilis is a perishable 

 plant and if preserved in a glass jar for 

 microscopic use, should be kept in a 

 cool place, should have a plenty of 

 room in the jar, and a free supply of 

 fresh water. 



[Mr. Balen informs us that he fully 

 agrees with Mr. Palmer as to the 

 beauty of the cyclosis in the plant 

 mentioned above. We have also seen 

 it, and can confirm all that has been 

 said concerning it. — Ed.] 



♦Gray's " Botany of the Northern United 

 States," page 482. 



A Note on Cupelopagis. 



Dr. Joseph Leidy has courteously 

 called my attention to some descrip- 

 tive remarks of his, reported in the 

 " Proceedings of the Philadelphia 

 Academy of Natural Sciences," Vol. 

 ix., p. 204, " relating to an animacule 

 found attached to stones in the Dela- 

 ware and Schuylkill rivers * * * * 

 closely allied in structure to the wheel 

 animacules, yet possessing no rotatory 

 or other ciliated apparatus." This 

 rotifer (which he names Dictyophora 

 vorax) is evidently closely allied to 

 the one described and figured by me 

 in the last number of this Journal, 

 and probably belongs to the same 

 genus. It is impossible to tell whether 

 the species is also the same without a 

 more detailed description, or a com- 

 parison of specimens. 



Dr. Leidy's generic name is, how- 

 ever, preoccupied in entomology, hav- 

 ing been used by Germar as early as 

 1833, for a genus of Hemiptera, and 

 even before him for a fungus ; and 

 that proposed by me, will therefore 

 have to stand. 



The word " pushed " in line 8, p. 

 102, second column, should read 

 " pursued," and the length of the body 

 should be given as 0.016, instead of 

 0.16. 



S. A. Forbes. 



Normal, 111., June 21, 1882. 



Thin Glass Cells. 



The Editor is not mistaken in say- 

 ing (in reference to the article on p. 

 loi), that Dr. Beale has described a 

 somewhat similar method of making 

 glass cells. Prof. Quekett, in the 3d 

 edition of his " Treatise on the Micro- 

 scope" (1855) says: "Dr. Beale recom- 

 mends the following plan: — ' One of 

 the thick glass rings, fig. 214, is heated 

 on the brass plate, and one side cov- 

 ered with marine glue. As soon as 

 the glue is melted, a small piece of 

 thin glass is carefully applied * * * 

 when cold, a semi-circular, or round 

 file is sharply thrust through the cen- 

 tre, etc' " 



