318 



THE AMERICAN MONTHLY 



[November, 



various structures connected there- 

 with. Nectar, as defined by the 

 antlior, is " a fluid always sapid, 

 usually sweet, often odorous, which 

 is elaborated in any part of a plant, 

 remaining where formed, or making 

 its way to some other part; its 

 raison d^Hre being the necessity 

 for the removal of some useless or 

 injurious substance, or for some 

 provision to attract nectar-loving 

 animals to the plant for some de- 

 finite purpose.'' Nectar is secreted 

 by glands which, when they occur 

 outside of the flower, consist of 

 modified epidermal tissues — within 

 the flowers their structure is more 

 varied. The floral and extrafloral 

 glands may occur as modifications 

 or appendages of various organs — 

 pistils' stamens, corolla, calyx, bracts, 

 involucre, peduncle, etc. The se- 

 cretion from floral glands seems 

 designed to aid in the fertilization 

 of Xhii flowers by attracting insects 

 or birds. This is true of the secre- 

 tion in the flower of the cotton- 

 plant. The same plant also secretes 

 nectar from the floral involucre. 

 During the night these glands are 

 visited by thousands of moths of 

 Aletia and /leliothis, when these 

 moths ai'e laying their eggs. As 

 the flowers of the cotton-plant suf- 

 fer from the attacks of the larvae 

 of those insects, it seems hardly 

 reasonable to suppose that the nec- 

 tar has been acquired by natural 

 selection to attract the enemies of 

 the plant. However, the secretion 

 also draws the enemies of the larva?, 

 and thus, perhaps, compensates in a 

 measure for the injury that would 

 otherwise result. Probably the 

 extra floral nectar M-as originally de- 

 veloped by natural selection, tliat it 

 might attract some animal to 

 protect the plant from the depre- 

 dations of some leaf or flower-eat- 

 ing creatures. The so-called "honey- 

 dew" is sometimes produced by 



Aphide.'< or plant-lice ; it is also 

 found as a product of the plant, 

 but is never secreted by glands. 

 Mr. Trelease considers, with Dar- 

 win, that all nectar was at first 

 merely an excretion, iind that the 

 material used in the elaboration of 

 nectar by large, specialized and 

 active glands, can be readily spared 

 by the plant without impairment of 

 its vigor. 



CORRESPONDENCE. 



OPHRYDIUM ADM. 



To THE Editor: — I wish to make 

 note of the fact that I have found in the 

 Niagara River, at Buffalo, N. Y., the in- 

 fusorium, Ophrydium adce, described by 

 Dr. Hermann C. Evarts at page i of the 

 January number of this Journal. I find 

 the jelly-like masses under the loose stones 

 along the pier, so far, only on the river 

 side ; the largest masses are about one- 

 third larger than those found by Dr. 

 Evarts ; those taken here have a larger 

 number of " chlorophyll granules " than 

 he ascribes to his. I have verified the 

 greater part of the excellent original 

 diagnosis. D. S. K. 



Buffalo, N. Y., Oct. 11, 1880. 



CARBOLIC ACID MOUNTING. 



To THE Editor: — Mr. Vorce's article 

 on " Carbolic Acid in Balsam-Mounting," 

 published in the September number of 

 this Journal, recommends an admirable 

 process which has been perfectly success- 

 ful in my hands, but one from which I 

 think an important item has been omitted. 

 The writer in Science Gossip, to whom 

 Mr. Vorce refers, says : " When I mention 

 carbolic acid, I mean the best crystallized, 

 which can be bought at any chemist, 

 who will, on being asked, add just suffi- 

 cient water to keep it fluid." This, to 

 me, seems important, unless Mr. Vorce 

 has been equally successful with the ordi- 

 nary solutions for sale by the druggists. 

 As there is considerable difference in the 

 price, will he kindly sav which he has used ? 



Trenton, N. J. ' A. C. S. 



NOTES. 



— Messrs. J. W. Queen and Co., of 

 Philadelphia, have prepared a series of 



