80 ENGLISH BOTANY. 



On dry banks and on rocks. Apparently rare. I have only 

 seen specimens from Bembridii^e Down, Isle of Wight, and St. Vin- 

 cent's Rocks, Bristol. The plant originally figured by Curtis was 

 found by Mr. Dickson near Croydon, Surrey. 



England. Annual. Spring. 



Stem dividing into several at the crown of the root, 1 to 3 inches 

 high. Lower leaves oblanceolate ; the stem-leaves usually narrower 

 than those of C. tetrandrum. The bracts at the base of the cyme 

 are much smaller in proportion to the size of the leaves, and the 

 upper bracts have distinct though very narrow scarious margins. 

 The flowers are less erect. The white scarious border of the sepals 

 is also much broader than in the last-named plant. The plant has 

 more non-glandular hairs intermixed with the glandular ones, and 

 the colour is a paler and yellower green, often tinged with dull 

 purple. The capsule is nearly twice as long, and distinctly curved. 



The Continental specimens are often considerably larger than 

 the dimensions given above. 



Dr. Walker Arnott, in Hooker's "British Flora," is inclined to 

 regard C. pumilum as the pentandrous or early-flowering state of 

 C. triviale ; but he appears to have seen no specimens, and only to 

 found his judgment on the figure in Curtis's " Flora Londinensis." 

 This figure is on the whole very good; but the capsule is repre- 

 sented as more than twice as long as the calyx, while in the speci- 

 mens I have had the o])portunity of examining I have always found 

 it a little less. This fact, and the colour of the plant in the plate, 

 have no doubt helped to produce the imj)ression that it belongs to 

 C triviale, from which it appears to be decidedly distinct, as the 

 sepals are acute, not obtuse, and the numerous glandular hairs 

 on the sepals and peduncles furnisli an obvious though not an 

 important distinction between it and the small annual state of 

 C. triviale. C. pumilum has been generally confounded with 

 C. semidecandruni, and I myself at one time fell into the eri'or of 

 considering it merely a state of that plant ; but when Mr. A. G. 

 More had sent me fresh specimens so as to permit an examination 

 of the petals, I was obliged to admit with him that it was almost 

 as nearly allied to C. tetrandrum, from which the chief points of 

 difference are the scarious margins of the bracts and broader 

 margins to the sepals, the much longer and more curved and 

 inclined capsule, and the reflexed pedicels; which last character, 

 however, sometimes, though rarely, occurs in C. tetrandrum. 



Curtis's Mouse-ear duckweed. 



Frencli, Ceraiste Kaiu. 



