1908] Araneae Theraphosae of California 223 



The burrow is much shorter than in Eutychides versicolor and 

 relatively of greater diameter, in proportion to the size of the 

 spider. The silk lining is thicker and whiter than in the other 

 genus. Three specimens had branches of the surface type, not 

 true lateral chambers. Above-ground extensions are common, 

 especially at Pacific Grove, and the variations described for E. 

 versicolor might be repeated here, it being practically impossible 

 to distinguish between the "turrets" and traps of the two species, 

 as to appearance and variable structure. The proportions of the 

 burrow and the thickness of the silk tube are to me the only clue 

 to the identity of the genus before the occupant is reached. The 

 largest burrow, that of No. 137, gave the following dimensions: 

 length, 20 cm. ; average diameter, 15 mm. ; trapdoor, 22x17 mm., 

 of soil, moss and grass-bits, and a small leaf. Some of the bur- 

 rows are surprisingly short, being only 10, or even 6, cm. long. 



Number 137 was taken Oct. 31, 1907, and had some sixteen 

 or more young, about 5 mm. long, running about in the deeper 

 end of the tube. Fourteen of these w^ere brought into the labor- 

 atory and placed in vials. Most of these burrowed into the soil 

 at once and made little trapdoors about 3 to 4 mm. wide. They 

 were not properly cared for, .but, almost two months after being 

 brought in, they replaced their doors when same were removed. 



It may be noted here that these young, direct from the 

 mother's burrow, both in this species and in E. versicolor, are 

 readily referable to their respective genera by the characters of 

 the cephalothorax and the abdominal markings; while the ster- 

 num, pedipalps and legs give no clue to the genus to which the 

 specimen belongs. This is significant, if the characters earliest 

 established in ontogeny are of most importance in classification. 



Eurypelma californica Auss. Verh. zool.-bot. Gessell. Wien., 

 1871, p. 214. 



(Plate XVII.) 



The genus Eurypelma is found in California at least as far 

 north as San Mateo County, in the outer Coast Ranges. It used 

 to be common about Stanford University, a few specimens being 

 deposited in the entomological collections here, but it seems to be 

 rare or local about here now. One or two are picked up and 

 brought in almost every year, two large ones having been taken 

 this year — one, a male, picked up while crossing a road (October), 

 the other, a female, found under a rock on the top of one of the 



