and is given below. The plants considered, are arranged in series, 

 probably to indicate their affinities, though it is not so stated. In the 

 following list, the series are separated by a dash, and the page on 

 which they are mentioned is given. 



Dr. Minks is the most vigorous opponent of the Schwendener 

 theory, that so-called lichens are only fungi parasitically associated 



with algae, who has yet appeared, 

 and exhaustive. 



His studies have been extensive 



Unfortunately, the style in which his views are ex- 

 pressed is so difficult as to be anything but attractive; and few in 

 this country, probably, will have the patience to read his work, Das 

 Microgonidium, in wliich his doctrines are conveyed. He has many 

 original opinions, some of which have not been verified by other 

 observers; but several have seen the microgonidium, the organ which, 

 according to Minks, is the fundamental one of lichen structure, and 

 which distinguishes it absolutely from all fungus structure. The 

 microgonidinm is an extremely small, simple cell, which, under 

 proper treatment, can be seen in all parts of lichens— in the hyphae, 

 the paraphyses, the spermatia, and the spores, and its history and 

 development are very fully treated in the work above-mentioned. 



^ A fe^y words will elucidate Dr. Minks's mode of treatment. A 

 thin section of the thallus or apothecium of a lichen is to be soaked 

 for a short time (from five to ten minutes), in liquor poiassae. It is 

 then to be washed and placed in dilute sulphuric acid for about 

 three-quarters of an hour, or until it becomes of the consistence of 

 soft putty. It is then to be placed on a sUde, in water, and a small 

 portion of solution of iodine added. With a suitable light, and suf- 

 ficient magnifying power, the microgonidiaare then visible, as minute 

 cells of a bluish-green color. Dr. Minks recommends the use of 



an immersion lens, and a magnifying power of looo, with the 

 reflected from a cloud. " " ' 



light 



It is the detection of microgonidia in the 

 tissues of the fungi enumerated, which leads Dr. Minks to include 

 them among lichens; and a wide field is here opened for those who 



use the microscope. 



I. 



Tympanis picastra, Berk & Curt 



2. T. Rave?}€ln^ B. & C. 



3. Phacidiutn elegans^ B. & C. 



Ala,^ p. ir 

 S. Car.^ p. 12 



N. 



5- 

 6. 



7- 

 8. 



10. 



4. Tympams viiicola, (Schwein) Fr 



T, fiisciculata^ Schwein. 

 Ce/Hutg!um Ccrasi, (Pers.) . 

 C. Magnoliae, B. & C. 

 Nodularia acericola^ Peck . 

 Dermafea carnea, Cooke & Elli^ 



11. D. carpinea^ (Pers). 



12. Patellaria Rubi^ Lib. 



13. Derinatea tabacina^ Cooke. . 



14. Cenangium iurgidum, Fr. 



15. Lecidea resinae^ Fr. 



16. Lecanidion fusco-atrum^ Rehm. 



17. Paieiiaria airata, {Utdvi.) . 



. N. /., p. 2,6 



N. /., p. 48 



. N, /, p. 48 



Mass., p. 52 

 Fla., p. 54 



N. v., p. 55 



, . JV. /., p. 56. 



Mass., JV. v., p. 59 



. JV. /., p. 63 



JV. J., p. 69 



N. £., p. 73 



. N. /., p. 81 



N. Y., p. 82 



