24 CALIFORNIA ACADEMY OF SCIENCES. 
xix backward and from segment xiii forward, the distance between the two ventral 
setee of each side gradually increases.” 
Distribution and habitat. The species of the genus Deltania described below 
are undoubtedly natives of the Pacific Coast of North America, and more particularly 
ef California. The species are found not only in the Golden Gate Park of San Fran- 
cisco, where they might have been introduced, but also in localities distant from 
gardens, and in which no cultivation has ever taken place. Thus I have species 
from Berkeley, Santa Rosa, Lake Chabot, Mount Diablo, ete. Moreover, since this 
paper was finished in MS., I have found species of Deltania in localities so far from 
civilization that there can be no doubt as to the native habitat. I refer to species 
found in the high mountains of the Cape region (in the vicinity of Cape San Lucas) 
of Baja California, at an altitude of 4,000 feet, in almost inaccessible localities. A 
species has also been found in a gulch or river-bed at Ensenada, Baja California, 
thus proving the extensive territory over which the genus extends. The description 
of these species must be deferred to another paper. 
As regards Deltania dubia (?Eudrilus dubius Fletcher) and Deltania Poulton 
(Microscolex Poultoni, Beddard) it may be possible that the former, at least, is an 
introduction from abroad. The locality where the latter is found shows the genus to 
possess a wide neotropic extension. 
While it is thus certain that species of Deltania are natives of the new world 
and the Atlantic islands, and especially of the Pacific Coast of North America and 
Mexico, the distribution of Microscolex must yet remain undecided. Whether it 
was imported from the Argentine Republic to the Mediterranean region, or vice 
versa, must remain an open question, though the finding of two species in the Medi- 
terranean countries seems to point to the probability of that region being its real 
habitat. 
Species. Of the genus Deltania, California now possesses at least three species 
with the very great probability of a discovery of new species, as soon as a wider area may 
have been explored. All the species appear very sensitive to dryness and heat and 
disappear with the first warm and dry weather, hence the difficulty of finding them 
except at their proper season which appears to be limited to February to April in the 
vicinity of San Francisco. The species in Baja California were found in September 
and October. 
Deltania elegans. 
Figs. 1-20, 49-58. 
Deltania elegans Eisen, Zoe, iv, 248, October, 1898. 
Size about 2 to 4 inches by from ,', to } inch wide. Septal glands very small, the 
posterior one the smallest. Spermathec very pellucid, minute, and irregular in their 
position both as regards somite and the place in the somite, but generally opening be- 
tween viii and ix. Sperm-sacs comparatively small, deeply lobed, one pair in xi and 
