228 The Irish Naturalist. [Sept., 



In their recent systematic works, Schott (ii) and Renter (lo) follow 

 TuUberg (12) in regarding T. longicornis of Miiller and Lubbock (4) as the 

 true T. plumbeus of Linne. The present species {T, plumhens, Lubbock) is 

 readily distinguished from other species of the genus by the trident- 

 like spines on the dentes of the spring. 



Cyphoderus Martelll, sp. nov. 

 PI. 2, figs. 6-10. 



Sinella cavernicola, Jameson (2) (for the most part). 



Antennae one-and-a-quarter times as long as the head, second segment 

 slightly longer than third, fourth segment still longer ; thorax with a 

 few clubbed hairs ; fourth abdominal segment three and a half times as 

 long as third (fig. 6). Upper claw of foot with a delicate but prominent 

 tooth ; lower claw three-quarters as long as upper (fig. 8, 9). Mucro of 

 spring short and recurved, as in Seira, bearing a strong tooth. Dens 

 with numerous long clubbed ciliated hairs (fig. 10). White, with a slight 

 3'ellow tinge. Length i -5 mm. 



Mr. Jameson took a large number of examples of this springtail, which 

 next to Lipura Wrightii, seems the dominant species in Mitchelstown 

 Cave. It may, I think, be safely referred to the genus Cyphoderus, Nicolet, 

 in its modern, restricted sense { = Beckia,'Li\xhhoc'k.), as it resembles the type- 

 species, C. albinos^ Nicolet, in the form of its antennae and the structure 

 of its feet. The mucrones of the spring however are relatively much 

 shorter than in C. albinos, and recall rather those of a Seira. 



I have already alluded to the French cave-species Seira cavernarum 

 described by Moniez (8) from the cavern of Dargilan. That insect 

 would seem to agree to a great extent with the present springtail in 

 the relative length of the abdominal segments, the structure of the 

 feet, and the mucrones of the spring. The antennae of the French 

 insect, however, are more than half as long as the body, and this pro- 

 portion seems to have led Moniez to place it in Seira rather than in 

 Cyphoderus in spite ofthe absence of eyes. 



The two European species of Cyphoderus, C. albinos, Nicolet, and 

 C. argenteus (Lubbock) are both blind, so it would seem that our Mitchels- 

 town insect is, in this respect, no more degenerate than its above-ground 

 relations. C. albitios lives in various concealed situations, and is often 

 found in ants' nests on the Continent. The blindness of various animals 

 which live with ants is well known, as in the case of gamasid mites, the 

 beetle Claviger and the woodlouse Platyarthrus', probably the darkness 

 and the ease of gaining a living in the ant-colonies render sight needless, 

 and so it may be that the blindness in the cave-species and in C albinos 

 has been independently acquired. It is noteworthy that according to 

 Joseph (3) C. albinos is itself an inhabitant of certain caves in Carniola. 



I have already indicated the diflference in the form of the mucrones of 

 the spring which separates our species from C. albinos. The third 

 antennal segment, moreover, is much longer relatively in C. Martelii. In 

 this last character the species resembles C. argenteus (Lubbock) (4), but it 



