118 



THE AMEKICAN MONTHLY 



[June, 



thing that does not contribute directly 

 to the formation of the adult animal 

 has been dropped out of its life-his- 

 tory. The monograph referred to 

 has been issued in pamphlet form, 

 and is well worthy of careful study, 

 being both interesting and instructive. 



Chroolepus and the Schwen- 

 DENER Hypothesis. — The March 

 number of the Brebissonia contains 

 a short article from Prof. J. B. 

 Schnetzler upon Chroolepus aureum, 

 Ktz., one of the aerial algie, which 

 seems worthy the attention of those 

 who are interested in the questions 

 regarding the nature of lichens, that 

 have recently been so warmly dis- 

 cussed in the cryptogamic periodi- 

 cals. We have scarcely space for the 

 entire article, but we translate and 

 condense parts of it as follows : 



" Upon moist rocks, in the vicinity 

 of Lausanne, small cushions are 

 found, formed by an aerial alga 

 {Chroolepus aureum, Ktz.). It is 

 formed of ramifying filaments, the 

 cells of which produce drops of a 

 yellow-colored oil instead of starch. 

 In the lichens belonging to the family 

 Graphideae, this alga is found asso- 

 ciated with a fungus which, like a 

 parasite, profits by the nourishment 

 prepared by the alga. 



" The alga which I have found pre- 

 sents an interesting fact. It is a per- 

 fectly independent alga. Upon the 

 rami, globular, lateral sporanges are 

 found ; but at the base and upon the 

 sides of the filaments one sees the 

 hyphae of a fungus in the form of 

 colorless filaments, which apply them- 

 selves to the cells of the alga, and 

 even penetrate them. These hyphae 

 form a plexus between the ramifica- 

 tions of the alga, and thus unite and 

 entangle them. 



" The fungus is therefore an in- 

 truder, which establishes itself upon 

 an independent alga. Little by little 

 it becomes master, and, thanks to 

 the nourishment afforded by its host, 

 the latter becomes completely envel- 

 oped." 



CORRESPONDENCE. 



To THE Editor : — I found a rich ponC 

 yesterday, and, knowing your desire to 

 publish localities of objects, I write you of 

 it. The pond is on the south-east part of 

 this city, and yesterday it was literally 

 alive with Chirocephalus diaphanus. 

 You will find them described in " Baird's 

 British Entomostraca," and referred to 

 there as rare. I do not know whether 

 they are rare in this country or not, but 

 this is my first view of them. I would 

 like to send some to you, but they 

 are very fragile and would not stand, 

 transportation — some died on my way 

 home. 



H. F. Atwood. 



Rochester, May 2d. 



NOTES. 



— Dr. R. U. Piper, of Chicago, who 

 •was in this city last month, urgently re- 

 quested us to publish a letter from Mr. A. 

 Montgomery, attorney in the case of Hen- 

 derson vs. Wm. Lill's executors, to which 

 reference was made by Dr. Lester Curtis 

 in his article in Vol. I, p. 124, of this 

 Journal. It seems rather late to bring 

 the subject again into notice ; it may be 

 stated, however, that the object of the 

 letter is simply to prove that the testi- 

 mony of Prof. Babcock, as given by Dr. 

 Curtis, was not presented in court, and 

 that Dr. Piper was the only microscope- 

 expert examined for the defendants. Prof. 

 Babcock's testimony related to the nature 

 of the ink, not to the characteristics of 

 the writing. 



— Probably all who have had occasion 

 to fix objects, such as diatoms, for ex- 

 ample, upon a slide, by means of gum 

 Arabic, have been more or less annoyed 

 by the granular appearance of the gum. 

 Mr. H. J. Waddington* obtains a solu- 

 tion of the pure gum, arabin, in this man- 

 ner: Selected pieces of gum Arabic are 

 dissolved in distilled water, so as to form 

 a thin mucilage. This is filtered, and the 

 filtrate poured into a considerable volume 

 of alcohol, which precipitates the arabin. 

 This is separated from the mother liquor 

 by filtration, washed with alcohol and 

 finally dried. It is freely soluble in water 



* Journal of the Quekett Club. 



