176 DUMONTIACEAE 
and imperfectly developed; this plant is only about 19 cm. high; 
its main segments are less flattened and are rather more rigid and 
corneous on drying; the plant is copiously infested with Lobo- 
colax and this fact may account for some of its peculiarities of form. 
No. 465 p.p. is a form with narrow segments (1-2 mm. wide) 
and has almost the aspect of a distinct species. In its narrowness 
it is slightly suggestive of Harvey's var. angusta of Prionitis 
lanceolata, which has been raised to specific rank by Setchell,* 
though the Peruvian plant is less elongated and is otherwise 
different in habit. 
Setchell and Gardnert have referred a Californian plant (Рус. 
Bor.- Am. 199b) to Prionitis decipiens, though it nanifestly differs 
considerably from the true Peruvian P. decipiens in color and habit 
and also, apparently, in having the tetrasporangia confined to 
lateral branchlets. 
PLATE 64. Prionitis decipiens i 
Photograph of а luxuriant long-pinnate specimen (Coker 402 ~.p.—from liquid 8 
preservative), reduced to about two fifths of Из natural dimensions. The | 
like the ext l thalli of a itical alga, Lobocolax deformans. 
PLATE 65. Prionitis decipiens ү 
Photograph of a shorter, stouter, more frequently forked and less pinnate speci- a с 
теп (Coker 144 $.5.—írom liquid preservative), reduced to about three fourths of | 52 
its natural dimensions. Тһе parasite, Lobocolax, is abundant arid has the appear- е 
ance of deforming Из host. ` | 
Family DUMONTIACEAE E. 
LEPTOCLADIA J. Ag. Anal. Alg. 95. 1892. Setchell, 
Univ. California Publ. Bot. 4: 250. 1912 * 
Andersoniella Schmitz, in Engler & Prantl, Nat. Pflanzenfam. m 
520. 1897. | 
наще вт ла 
Leptocladia peruviana sp. nov. 
* Phyc. Bor-Am. no. XXIV. Л 1899. The name, however, is preoccupied PY 
the different Prionitis angusta (Harv.) Okam. (Bot. Mag. 13: 4. 20 Ja 1899) | 
T Univ. California Publ. Bot. 1: 350. 1903. 
