A NEW KOENENTA Fl^OM TEXAS. 225 



consideration. From an analytical standpoint, the presence 

 of these lung-sacs in some species only, seems sufficient 

 ground for a definite and well-marked division of the genus 

 Koenenia into two sub-genera. Mr. Borner ^ was the first to 

 make the suggestion, basing the distinction on the condition 

 of the reproductive appendages. Unfortunately he was 

 misled, by Dr. Wheeler's mistaken description of the male for 

 the female, into believing that the appendage of the second 

 abdominal segment in K. wheeleri was paired, and repre- 

 sented a more primitive condition ; hence he placed K. 

 wheeleri under the sub-genus Prokoenenia, while the then 

 only other known species, K. mirabilis, he placed under 

 the sub-genus Eukoenenia. However, inasmuch as I\. mira- 

 bilis presents a slightly paired or notched condition of the 

 reproductive appendage, and inasmuch as K. wheeleri 

 passes through a stage in its development ~ which is more 

 nearly comparable to K. mirabilis, their position in the 

 sub-genera would have to be reversed if we attempt to carry 

 out Mr. Borner's suggestion. With his permission, then, I 

 adopt his sub-genera Prokoenenia to include all species 

 possessing lung-sacs, and Eukoenenia to include those species 

 not possessing lung-sacs. 



In regard to exact characters indicative of the species, 

 further observations will have to be made before anything 

 like a definite and concise analytical table can be arranged. 

 Of the three species which I have been able to examine and 

 compare — K. wheeleri, K. mirabilis, and K. florencias 

 — the relative size of the three more distal seta3 of the 

 proximal joint of the cheliceras was a prominent and charac- 

 teristic feature of the species. In descriptions ^ of the other 

 four species no stress is laid on the distinction ; and the setve 

 are figured in only one of the species, K. angusta. For the 



' "Zur iiuf seren Morphologic von Koenenia mirabilis, Grass!," aus 

 dem ' Zoologi&chen Anzeiger,' Bd. xxiv, No. 652, p. 551. 



^ ' Zoologisclie Jahrbiicher,' 1903. 



* "On Six Species of Koenenia, with lleniarks on llie Order Palpigradi," 

 H. J. Hansen, ' Enloniologisk Tidskril't,' 1901. 



VOL. -17, PART 2. — NEW SERIES. P 



