—35— 



been found by Miss Annie Lorenz, who, by the way, states that at West Hart- 

 ford, Connecticut, plants of this species persisted alive through the unusually 

 severe winter of 19 14 and that the species is apparently a perennial. Besides 

 Massachusetts, Connecticut, New Jersey, and Georgia, the species has been 

 found also in Illinois, Florida, Texas, Colorado, California, and Alberta (Brink- 

 man). Under the name Riccia Lescuriana several European hepaticologists 

 have attributed the species to Europe also, and as is the case with several other 

 species in this genus, it seems impossible to separate some of the European mater- 

 ial from the American. However, some of the non-ciliated European specimens 

 that have been referred to R. Lescuriana seem to be more closely related to 

 Riccia glauca or R. bifurca than to this species. 



Riccia McAUisteri sp. nov. 



Thallus 2 or 3 times rather divergently forking, often forming densely gre- 

 garious more or less radiating masses, bright green when living, often whitish- 

 or yellowish-green with age or on drying, violet-purple or sometimes decolorate 

 at margins and on sides, regularly reticulate above, 5-8 mm. long, the main seg- 

 ments oblong or oblong-obovate, 1.5-2.5 mm. wide, the terminal segments ovate, 

 subquadrate, or somewhat obcordate, rounded-obtuse or subacute; median 

 sulcus acute and sharply defined in anterior parts, becoming obscure in the 

 posterior; ventral scales entire, reddish violet, claret-colored, or sometimes de- 

 colorate, imbricate, slightly exceeding the acute ascending margins, the extreme 

 margin hyaline or violet and unistratose for a width of one or two cells; trans- 

 verse sections of the thallus mostly 2-3 times broader than high, the ventral 

 outlines rounded-convex or occasionally somewhat flattened; dorsal epidermis 

 of two (or three) layers of cells, the cells of the primary stratum mostly mammi- 

 form-apiculate, soon collapsing and leaving rather inconspicuous, or sometimes 

 cup-like vestiges, the cells of the secondary superficial stratum mostly 26-78^ 

 broad, these and underlying cells in very distinct and regular rows when viewed 

 from above; monoicous; antheridial ostioles elevated 50-160/x, often violet; cap- 

 sules usually numerous, soon exposed, the spores lying conglobate in long masses 

 at the bottom of a deep widely open pit or trough; spores at first violet or violet- 

 .brown, soon violet-black and opaque, 96-132^4 in maximum diameter, ellipsoid, 

 ovoid, subspheric, or obscurely tetrahedral, wholly destitute of wing-margins, 

 at first almost uniformly areolate over the whole surface, the areolae mostly 7-1 5m 

 in diameter, soon obscure, and the spores finally appearing densely echinulate, 

 the spinulae 5-1 Im long, truncate or obtuse, or occasionally subacute, sometimes 

 cristate-furcate. 



On moist ground near standing water in quarry-holes. Granite Mountain 

 (about 70 miles northwest of Austin), Texas, Dr. F. McAllister, May, 1914. 

 The technical type specimens were grown in the Propagating House of the New 

 York Botanical Garden, whence they were collected and placed in the herbarium 

 of that institution on December 8, 19 14. 



Plants that are doubtless to be referred to this species have been collected 

 also at Glencoe, Missouri, by Dr. N. L. T. Nelson (in herb. A. W. Evans), though 

 its spores are rather more obviously reticulate and less strikingly echinulate 

 than those of the Texan type. 



Riccia McAUisteri is related to R. dictyospora M. A. Howe, originally de- 

 scribed from Athens, Georgia, yet appears to be specifically distinct, differing 

 in the less elongate, less linear, less conspicuously marginate, more freely fork- 



