288 University of California Publicati-ons in Botany [Vol.7 



have crisped oi' nifflcd edges. This description is taken largely from 

 Jessen (1848, p. 19, \)\. 1, figs. 17-20), who, as noted above, received 

 his materials from the type collection directly from Liebmann, the 

 oi-iginal collector. Unfortunately we have not been able to examine 

 any of the type material and, consequently, must judge our plants 

 entirely from the point of view of the descriptions and figures. From 

 tliis point of view it seems safe to refer most of the various specimens 

 accessible to us to P. mexieana. 



Under Prasiola mexieana have thus been referred specimens from 

 Montana (Tilden, Amer. Alg., no. 129), Wyoming (Tilden, loc. cit., 

 no. 555«) and Oregon (Tilden, loe. cit., no. 5556, and Collins, Holden 

 and Setchell, Phyc. Bor.-Amer., no. 1186). The species is represented 

 in the Herbarium of the University of California by specimens from 

 "Washington (no. 132922, collected by Professor T. C. Frye in the 

 Ehoha River in the Olympic Mountains), from Oregon (no. 98182, 

 from McCleary Canyon near Portland, collected by A. S. Foster ; nos. 

 98181 and 98183, collected near Eugene and near Forest Grove re- 

 spectively by Professor A. R. Sweetser), while in California it has 

 been collected in Crane Creek above El Portal at an altitude of 4000- 

 4500 feet (Gardner, no. 4466). It is reported by Wolle (1887, p. 107, 

 pi. 91, fig. 24) from Colorado, where it was collected by T. S. Bran- 

 degee. It has also been collected in the Diamond range of mountains 

 in eastern Nevada, where it was found by Sereno Watson and de- 

 scribed by Horatio C. Wood (1871, p. 415, 1873, p. 182) under the 

 name of Viva merismopedioides. A portion of the type (or cotype) 

 has been examined and there seems little question as to the identity 

 of Wood's species and those we are assigning to Prasiola mexieana 

 J. Ag. The fragment of the type examined and from which our 

 figures (cf. pi. 21, figs. 8-10) are drawn for comparison was communi- 

 cated to us by Frank S. Collins, having been received by him from 

 the United States National Herbarium. Collins (1903, p. 17) placed 

 the Viva merismopedioides Wood under Manostroma quaternarium, 

 but later, as he writes us, made a second examination of the material 

 and found something seemingly different from what he had examined 

 previously and upon which he had based his oj)inion. The fragment 

 examined by us is clearly Prasiola mexieana as we understand that 

 species. The crass-section of Wood's plant, however, differs from the 

 description of Wood in that the cells (cf. Wood, 1873, p. 182) are not 

 in a single layer, but in two to several, as a glance at our illustrations 

 (ef. 1)1. 21, figs. 9, 10) will show. 



