Pomona College, Claremont, California 3 



Hie long process oi the coxa clothed with its long simple hairs 

 seems to have some performance in the work oi the mouth parts. 



The labium is suboval, clothed thickly with simple short hairs., the 

 upper margin having a single row oi long heavy straight hairs 

 with many long single curved hairs covering them. 



The mandibles are provided with three distinct kinds oi hairs 

 or spines. Idie large subquadrate proximal joint was clothed with 

 long barbed spines, the movable finger having on its median sur- 

 face a row ol fifteen back curved barbed spines. In the space 

 between the movable and stationary finger were long hairs, en- 

 larged in the center and tapering off to a line point, the tapered 

 portion being barbed. The mandibles are set well down in the 

 sephalothorax. 



The sexual openings were found in the usual place; the ventral 

 surface oi the first abdominal segment, this being enlarged so as 

 to do away with the second abdominal segment. I he epigynum 

 consists ol a long epigastric furrow with a large lip-like opening 

 near its median line. Just above this opening and on either side 

 were small longitudinal creases. 



Prof. \)\\ Friedrich Dahl places the external sexual organs of 

 this family on the legs and in the rhelyphonidae which is closeK 

 related. They are found in the second joint of the tarsus ol the 

 first legs. Careful study tailed to lind any trace ol secondary sexual 

 organs in Trithyreus pentapeltis. 



Krayselin, Karl 1899 



Das Tierreich. Scorpiones und Pedipalpi. 



Cook, O. F. 1899 



Hubbardia, a new genus of Pedipalpi, Entomological Society Proceed- 

 ings, vol. 3. 



Comstock, John Henry 1911 



The Spider Hook, pp. 17- IS. 

 Banks, Nathan 1900 



Synopsis of North American Invertebrates. Am. Nat. Vol. .-!4. 

 Dahl, Dr. Friedrich 19 13 



Vergleichende Physiologie and IVIorphologie Der Spinnentiere. 

 Jena, Verlang N. (r. Fischer. 



(Contribution from tin Zoological Laboratory of Pomona College.) 



