414 Rev. "W. A. Leighton on the Determination oj the 



gida, and approaches C, furcata in the same way as turgida 

 ■ approaches to pungens. C. grypea has K — . 



33. C. cenotea, Sch8er. = Fr. L. S. 55 (fide spec, a Nyl.) ; Auzi, 

 C. C. 20 ; Zwackh. 329 ; Massal. 156 ; Sch^r. L. H. 71 ; Coem. 

 CI. Belg. 116, 117, 118, 119. 



My herbarium also comprises specimens from Upsal (Dr. W. 

 Nylander and Dr. T. M. Fries), Jerkin, Norway (Dr. "W. L. 

 -Lindsay), Untersontheim (Kemler), Mahourat, Pyrenees (Mr. 

 Spruce) . 



Var. ^/awcffl, Flk. = Schser. L. H.460; Zwackh. 330; Coem. 

 Clad. Belg. Ill, 112, 113, 114, 115 ; Coem. 1028. 



I have it also from Untersontheim (Kemler). 



34. C. squamosa, Hoffm. (E. Bot. t. 2362) = M. & N. 645 ; 

 Anzi, C. C. 21, A, c ; Schter. L. H. 72, 73, 278 ; Massal. 292, 

 A. C. ; Mudd, L. Br. 13 ; Tuck. 30 ; Coem. *1025, 1026, 1027 ; 

 Zwackh. 379 ; Mudd, Br. CI. 40, 41 (part.), 42. 



In my herbarium are also specimens from Upsal (Dr. T. M. 

 Fries), Kirjavalaks, Finland (Kullhem), Untersontheim (Kemler), 

 Pyrenees (Dr. Deakin), Mount Gaillard, Pyrenees (Mr. Spruce), 

 Subat (Dr. Philippe), Bagni di Lucca (Dr. Deakin), Nisay 

 (Breutel), Leicestershire (Rev. A. Bloxam), and Shropshire. 



Here is another instance of two diiferent plants being united 

 by external characters under the same name, but which are 

 readily separated and arranged properly by the hydrate of 

 potash. 



Dr. Nylander {in litt.) remarks that the name squamosa, being 

 the best-known and the most common one, ought to be defi- 

 nitely reserved for that lichen which is the most developed, i. e. 

 that which does not manifest the yellow reaction with the 

 hydrate of potash. The lichen, on the contrary, the cortex of 

 whose podetia becomes yellow with this reactive (K+), and 

 which has frequently the aspect of squamosa, but is much more 

 rare, can be nothing more than a variety {luxurians or suhsqua- 

 mosa) of C. delicata, which, by the reaction (K + ), shows itself 

 to be distinct from squamosa (K— ). 



In the herbarium of Delise, Dr. Nylander has noted with the 

 reaction K— the following varieties of his squamosa, \\z. tenui- 

 uscula, scabrosa, simplex, muricella, crassa, elegans, paschalis, 

 frondosa, flahellata, rigida, as well as his type of this species. 

 The same absence of reaction is visible in his C. cucullata (which 

 scarcely difiers from squamosa, var. frondosa, and which Dr. Ny- 

 lander says he has, in his Syn. p. 210, incorrectly referred to 

 delicata) and speciosa. 



On the other hand, the yellow reaction (K+) is observed in 

 C. delicata and its varieties in the herbarium of Delise as well as 

 in his C. syrtarum and C. squamosa, var. anomaa, Del, - 



