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Latreille divided the Pedipalpi into 2 genera: Phrynus and Thelyphon- 

 us. Since then numerous species have been collected and new genera 

 have been proposed. Koch establishes for the genus Thelypho7ius the 

 family Urotrichiox Whiptails and Karsch for Phrynus the family Tarantula 

 with the genera Phrynichus, Tarantula, Damon and Charon. 



Lucas described in his monograph 7 species of Thelyphonus, amongst 

 which is T. giganteus which is found quite frequently in the Southern 

 States, where it is much feared by the people who call it Nigger Killer, 

 Mule Killer, Grampus, etc. Girard found a new species in the collection 

 of the Red River Expedition 1S52, which he called Thelyph. excubi/or, 

 and for which he gave no locality. This species seems to be very rare, 

 for it is mentioned nowhere since in print, nor have I ever seen more 

 than one although more than 20 specimens of giganteus came under 

 my observation. This one is in my own collection and was received 

 some time ago from Texas with a number of specimens of the other 

 species. 



In examining this little collection I found the following interesting 

 facts: 1, that excubitor is the male oi giganteus; 2, that they have not 

 as stated by all authors hitherto, 8 eyes, but 12; 3, that they are per- 

 fectly harmless as they possess no poison glands in their mandibles. The 

 reasons for this assertions are: 1. The structural differences between both 

 species are exactly such, as are found between the sexes of the scorpions: 

 viz. in the male the tail and the palpi are longer and the abdomen more 

 tapering toward the apex. There is no other difference in structure found. 

 In opening the abdomen of two giganteus I found them filled with eggs 

 or remnants of such, which was not the case in examining the abdominal 

 cavity of excubitor. The external opening of the sexual organs present a 

 great difference of structure, for while in all giganteus the vulva appears 

 as a closed bursa the sexual orrifice in excubitor is not closed but repres- 

 ents a slit, divided vertically by a bar with two arch-like prominences. 2. 

 The fact that 2 eyes on each side have hitherto escaped the notice of natur- 

 alists, has for its reason, that they are extremely small in comparison with 

 the three large eyes between which they stand. Beside the two anterior ocelli 

 which stand in the median line near the clypeus, there is on each side 

 of the cepha'x and further back than the front eyes, a tubercle upon 

 which these 5 ocelli are situated: one small one at the tip of the tubercle, 

 one large one at its external side and one of medium size at the posterior 

 slope. Between these two latter ones are two very small ocelli, the 

 anterior of which stands a little higher than the posterior one. These 

 small ocelli are quite distinct and shine with the same bright amber color 

 out of the nearly black background of the tubercle. 3. That they have 

 no poison gland in the mandibles, I can only prove by the absence of 



