MELANTHACEJE FROM THE GENETIC STANDPOINT. igl 
2. CHLOROGALUM PARVIFLORUM, S. Wats. in Proc. Amer. Acad. xiv. (1879) 
243. 
Laothoe parviflora, Greene, Leaflets Bot. Obs. i. (1904) 91. 
S. California, San Diego Co. 
3. CHLOROGALUM ANGUSTIFOLIUM, Kellogg, in Proc. Calif. Acad. ii. (1863) 
105, t. 30. 
Laothoe angustifolia, Greene, Leaflets Bot. Obs. i. (1904) 91. 
Middle California, Sacramento Valley, and Mendocino Co. 
4. CHLOROGALUM PURPURECM, T. S. Brandegee, in Zoe, iv. (1893) 159. 
Laothoe purpurea, Greene, Leaflets Bot. Obs. i. (1904) 91. 
California, Coast Range, Monterey Co. southward. 
The genus CAlorogalum contains four species and is practically confined 
to California. The following key, compiled by Mr. C. H. Thompson, shows 
the nature of the specific differences :— 
A. Bulb large, thiekly coated with coarse brown fibres; perianth-segments narrowly 
ligulate, spreading widely from the base in the open flower. C. pomeridianum 
(Ker), Kunth. 
B. Bulbs smaller, with membranaceous coat; perianth-segments spreading from above 
the base. 
a, Perianth-segments oblong-ovate; pedicels as long as or longer than the perianth ; 
flowers purplish blue. C. purpureum, T. S. Brandegee. 
b. Perianth-segments oblong-lanceolate ; pedicels very short. 
a. Flowers pinkish ; ovary broad and obtuse. C. parviflorum, S. Wats. 
B. Flowers white with yellowish-green lines; ovary oblong-ovate, acutish above, 
short stipitate. C. angustifolium, Kellogg. 
In C. pomeridianum the branches are spreading, the stems dark brown, and 
the leaves remarkably undulate. C. angustifolium differs in having narrow 
linear-lanceolate leaves, slightly undulate, and a bulb which is ovo-conie 
rather than long-ovate. 
C. pomeridianum and C. angustifolium apparently have much the same 
range in central California, the latter occurring chiefly farther inland in the 
Sacramento Valley, while the former extends farther northward into Oregon. 
The other species are more local in distribution and probably more recent in 
origin, as they are in discovery. C. parviflorum occurs in the extreme south, 
in San Diego Co., and C. purpureum in the Coast range of Monterey Co. 
This would be an interesting genus for experiments in cultivation, but 
until such are instituted it is superfluous to comment further on the specific 
differences exhibited, except to say that there is an unusual range of colour 
variation for so small a genus. 
21. ODONTOSTOMUM, Torr. 
A monotypie genus of western North America. 
OpoxrosroMUM Harrweeu, Torr. in Pacif. R. R. Rep. iv. (1856) 150, t. 24; 
Baker, in Journ, Linn. Soc., Bot. xi. (1870) 436. 
LINN. JOURN.—BOTANY, VOL. XLIV. y 
