24 



are iuoil' or less exclusively spinninj^ organs, w liile lliose ol' ('.hthonius C. K. and 

 Obisium 111. have a spinning, bul especially a predatory I'unctlon; if this explana- 

 tion is a correct one, a difference in habit must be found according to the structure 

 of the antennae not only between a CJiclifer Geof. and a Chthonins C. K., but also 

 between an Ideoroncus Balz, and an Ohisium 111., a Garijpns Floridensis Hks. and a 

 G. irrugatiis Sim., and between llic se.\es of Chelifer Geof. I have set forlh this 

 preliminary explanation to stir up those, who have any opportunity tor it, to direct 

 observations in nature for the purpose of settling these (juestions. It must be 

 regarded as pretty certain, that at least the flagelluni has a sensory function; but 

 of what nature and in what degree it differs in the difTerenl forms, would not be 

 worth the while to speculate on. 



Tulk startes in his interesting little treatise (30. p. 56) the very remarkable 

 theory, that the serrulae and the tlagellum are used in the cleaning of the niaxillar 

 chelae. As his observations are often so remarkably advanced, and as he says, 

 that he has observed Chthonius orthodactylus Leach do so several times, I thought 

 it worth while to make direct observations on Obisium inuscorum Leach., as soon 

 as material was available, to negative or confirm this supposition. I observed to 

 my surprise and pleasure, that specimens of this species would clean its large 

 chelae, as soon as a lump of moisl earth had become attached to them, by opening 

 the fingers of their antennae and drawing the fingers of the palps several times 

 between those of the antennae. Bouvier has observed , that Gargpus saxicola 

 Wath. has a similar, but slightly different manner, in which to clean its maxillar 

 chelae; he writes (5L p. 306): „ils ont notamment l'habitude de nettoyer les doigts 

 de leur pinces en les faisant glisser entre les deux chélicères ou entre les deux 

 branches d'un chélicère." It would be most interesting to observe the manner, in 

 which species of Chelifer Geof. clean their maxillar chelae; the structure of the 

 lamina interior seems not to be well adapted to such a procedure. Do species of 

 Chelifer Geof. perhaps clean their large chelae by drawing their fingers between the 

 two antennae only, and not between their fingers? Is the presence of a lamina 

 exterior in all the Panctenodactyli and its absence in most Hemictenodactijli to be 

 explained in this way? 



3. Maxillae. 



Introductory Remarks. 



While a good many authors have studied the structure of the antennae, 

 only a few have taken notice of the maxillae and labrum. Menge is the first, who 

 dealt with this question, but his representation is nol very good (1855. 33. p. 12). 

 Croneberg gives later on (l.S.SO. 38. pp. 290—292) a fairly good description of these 

 organs in -'Chelifer', as well as in ''Chernes" (1889. 45. pp. 421— 424). H.J.Hansen 

 studied the same organs in Obisiiiin inuscorum Leach (1884. 7. p. 103), and so did 



