18 The Graspedosotnatidde of Noj'th Avierica. 



also olfactory organs. They would enable the animal to detect 

 substances suitable for food, being always near the ground, and 

 directl}^ in front of the mouth. They are found in all Chilog- 

 natha, but in Craspedosomatidse are best developed. The}^ are 

 not so much as usual confined to the apices of the structures on 

 which they are placed, occupying nearly the whole lateral edge 

 of the exterior process of the stipes. 



2. The interior Cone of the Lingual Lobes. — This is larger and 

 longer than the others, directed mesad and somewhat curved in 

 that direction. It is sharp-pointed and apparently of homo- 

 geneous structure, no lumen being apparent. Its special func- 

 tion, if anj^ must be different from that of the other cones. 



3. The Styliform Processes.— Near the anterior-interior corner 

 of the lingual lamina is a peculiar, usually more or less tri- or 

 quadri-dentate structure apparently consisting of a solid piece of 

 chitin. This does not appear to exist in the other described 

 families of diplopods, except in some Polydesmidse (e. g., Scyto- 

 notu^s). We have no notion of any purpose it could serve. 



4. The Bristles of the Gnathochilarium. — On the lower surface 

 and lateral edges of the gnathochilarium are a few hairs of greater 

 size than the others, and with enlarged bases. They are probably 

 tactile in function. 



5. Probable Taste-pits. — The chitinous covering of the lingual 

 lobe is on the superior side extended backward over the ends of 

 the lingual laminae. This extension consists of a chitinous rim 

 enclosing an oval space covered 'by a transparent membrane in 

 which are scattered numerous pits, each surrounded by a chitinous 

 ring. These are shown in fig. 62 as they appear in Gonotyla 

 fischeri. 



V. — The Dorsal Setae. 



These structures characteristic of the family are of transparent 

 chitin, narrowly conic, with an enlarged base which fits into the 

 socket of the setigerous tubercle. Sections show that the setse 

 are hollow, and that the chitinous exo-skeleton is interrupted by 

 an aperture in the middle of the socket. 



The median pair of setee of the last segment are diflferent from 

 the others in that there is a more broadly conic base tipped with 

 a slender hair. The function of these may be different from that 

 of the others, though what the function of either can be is hard 



