— 70— 



colored plates, half-tones, and drawings that are both artistic and accurate, it 

 is a delight to the eye. Containing all our species, described in a clear and 

 interesting manner, it is a book that the amateur must have and the profes- 

 sional will have. The illustrated key is a feature novel and invaluable ; the 

 idea is so good that we hope to make use of it for the mo.sses. A. J. G. 



NORTH AMERICAN THUIDIUMS. 



Bv G. N. Best. 



The Thuidiums are widely distributed and 

 among the most common as well as the most 

 beautiful of mosses. The stems of these 

 plants are complanately branched, pinnate, 

 bipinnate, rarely tripinnate. In most species 

 the branches are so closely set as to give 

 them a plumose appearance which is some- 

 what distinctive. Although multiform, the 

 paraphylliaare more or less linear or filamen- 

 tose, often divided and branched, but not 

 foliose. The ovate-triangular stem leaves 

 are usually papillose on both surfaces, uni- 

 costate, the costa passing the middle. The 

 median leaf cells vary from roundish quad- 

 rate-hexagonal to rhombic-oblong; in two 

 species linear-rhomboidal. The capsules. 

 Fig. I. a, Thuidiumdelicatu- on smooth pedicels, are annulate, more or 

 lu7n X I. b, T. scitiim x i. c, less curved. The opercula vary from conic 

 Capsule of the same x 5. T. to rostrate; the peristomes well developed; 

 abietini{tn x i. the endostomial band "3 the length of the 



teeth with segments and cilia. 



SYNOPSIS OF SPECIES.* 



*The species mentioned in Lesquereux & James' Manual of the Mosses of North 

 America and here omitted, are as follows : Thuidium erectum is T. delicatulum ; T. 

 calyptratum is a form of T. microphyllum ; T. Alleni is a dubious sterile form probably 

 of T. delicatulum ; T. remotifolium is not a Thuidium and T. tamariscinum is not 

 known from North America. 



Apical cells of branch leaves crowned 



with 2-4 papillae (Fig. 2, a and b); 



median cells quadrate-hexagonal to 



oblong-rhomboidal (Fig 5) A 



Apical cells of branch leaves with a 



single terminal papilla (Fig. 2, c) ; 



median cells as in A. Paraphyllia 



numeros, branched B 



Apical cells of branch leaves not papillose ; median leaf cells linear- 



rhomoboidal (Fig. 10). Paraphyllia long linear or filamentose (Fig. 3, c). . .C 



