I897-J Carpenter. — The Collembola of Mitchehtown Cave, 227 



FAMILY SMYNTHURID^. 



Smynthurus coecus, TuUberg (12) 



PI. 2, figs. 11-15. 



The single specimen of Smynthurus found by Mr. Jameson, being white 

 in colour and destitute of eyes, might naturally have been supposed to 

 belong to a typical cave-species. The very characteristic spring (figs. 

 14, 15) with the elongate mucro, two-thirds the length of the dens, 

 ending in a rounded knob, agrees exactly however with Tullberg's 

 figures (12, pi. iii., ff. 24-5) of Smynthurus ccecus, a species found by him in 

 flower-pots in Sweden, and since recorded by Renter (10) from Finland. 

 TuUberg states that this species is without eyes, and that its body is 

 white with red spots. No trace of such markings is to be seen on the 

 Mitchelstown specimen, but the disappearance of pigment would be a 

 natural result of underground life, and is not of more than varietal 

 value. 



The antennae of this species are long, the fourth segment being nearly 

 as long as the second and third together ; the third is greatly thickened 

 specially at the proximal end ; the fourth, as in many Smynthto-i, is 

 ringed and provided with whorls of clubbed hairs (fig. 12). The feet 

 are destitute of clubbed hairs ; the upper claw is simple, while the lower 

 claw carries a small tooth near its base, and a long threadlike process 

 near its point (fig. 13). 



As mentioned above, Smynthurus ccecus is an addition not only to the 

 fauna of Mitchelstown Cave, but also to that of the British Islands. So 

 minute an insect — its length is only about 7 mm. — might be very readily 

 overlooked, and it probably awaits discovery above ground in similar 

 situations to those it affects in Sweden and Finland. It is possible, 

 however, that, like so many other animals of northern range it will be 

 found characteristic of Ireland, perhaps even altogether absent from 

 England, though it should almost certainly be found in Scotland. Mr. 

 Jameson's collection of the cave-insects was so extensive that he would 

 probably have taken more than a single individual if the species had 

 colonised the cave to any extent. Joseph (3) has described four species 

 of Smynthurus from the Carniolan caves, to one of which he gives the 

 name S. ccecus. He states, however, that it is nearly related to S. fuscus^ 

 Nicolet, which is a Papirius, not a true Smynthurus. 



FAMILY ENTOMOBRYIDJE. 



Tomocerus tridentlferus (TuUberg). (12). 



T.flumbeus, Lubbock (4) nee Linne. 



Messrs.Wright and Haliday found a springtail in the Mitchelstown Cave 

 which they referred to this species (13). Mr. Jameson obtained several 

 specimens not differing in any particular from the examples of this 

 common species which one finds above ground. He remarks (2) that 

 the insect seems equally at home in caves or in the upper world under 

 stones. Packard (9) has recorded this springtail from North American 



caves.'. 



A 2 



