The Systematic Position of the Genus Iladrotarsus. G19 



LXXXIII, — The Systematic Position of the Genus 

 Hadrotarsus, Thorell. By R. I. POCOCK. 



The type of the genus Gmogala, Keys., namely G. scara- 

 hceits, Keys., from Sydney, is in the British Museum. It 

 was described in 1890 in the last part of L. Koch's work on 

 the spiders of Australia. The description is defective in 

 many points, erroneous in others. Hence I oflfer the following 

 supplementary remarks on this interesting little genus *. 



Simon (Hist. Kat. Araignees, i. pp. 305-307, 18v)2) rightly 

 surmised that the type of GniogaJa was related to that of 

 Iladrotarsus, Thor. On the strength of Keyserling's descrip- 

 tion of Gmogala sca7'abceus he kept the two genera distinct, 

 but united them in the family Hadrotarsidse. In my opinion 

 there is no doubt that the two genera are identical. 



In Gmogala scarahaus, as in Hadrotarsus babirussa, the 

 eyes of the anterior line are procurved, the medians being 

 considerably larger than the laterals. Keyserling erroneously 

 describes the anterior eye-line as recurved, with the medians 

 smaller than the laterals. His figure and description of those 

 of the posterior line are approximately correct. The clypeus 

 is high and its inferior edge overhangs the base of the man- 

 dibles. The latter are vertical, not convex in front, with 

 their inner edges obliquely diverging externally from near 

 the base ; the fangs are long, arcuate, lying transversely and 

 crossing each other in the middle line. The labium is trian- 

 gular, wider than long. The maxillaa are oblique and meet 

 in front of the labium, their inner extremities being mem- 

 branous and pellucid. This pellucid area was apparently 

 overlooked by Keyserling, who represents the maxillfe as 

 widely separated in the middle line. The sternum is very 

 wide and convex, and projects between the posterior coxjb, 

 which are widely separated. The metasternite is thickly 

 chitinized and relatively large. Similarly the dorsal sclerite 

 of the pedicle is thickly chitinized. The anterior extremity 

 of the abdomen forms a circular rim above and below the 

 pedicle. The dorsal scute does not extend to the posterior 

 end of the abdomen, four transversely arched integumental 

 folds intervening between it and the anal tubercle. These 

 folds are continuous with the longitudinal folds that run 

 along the sides of the abdomen between the dorsal and 



* Having only one specimen for examination I was unable to deter- 

 mine certain important structural features, notably the dentition of the 

 mandibles, the structure of the sderites of the pedicle, &c. 



