42 The Irish NaJu?alist. February, 



ON SOME TERRESTRIAL ISOPODS FROM THE 

 GLASNEV^IN BOTANIC GARDENS, DUBLIN. 



BY RICHARD S. BAGNALL, FES. 



On the occasion of the visit of the British Association to 

 Dublin last year, I had the opportunity of doing a little 

 collecting in the neighbourhood of that city, and on Monday, 

 September 6tli, spent an hour with Mr. Pack-Beresford in the 

 Glasnevin Botanic Gardens searching for woodlice. Owing 

 to the kindness of the keeper, Mr. Moore, in giving us^every 

 possible help, we were able to find a number of good species, 

 though the time at our disposal was short. It is quite evident 

 that further and more systematic search will bring to light 

 other interesting woodlice, but as four of the species, Tricho- 

 717SCUS sp., Tricho7iiscus Stebbingi, Patience, Haplophthabnus 

 danicus, B.-L-, and Armadillidiiim nasaium^ B -L^-, do not 

 appear to have been recorded from Ireland, I think it desir- 

 able to record them here. 



TRICHONISCID^« 

 Genus Trichonlscus, BraiuU. 



Trichonlscus sp. nov. (?). 



I took possession of a very minute and distinct form, which I had the 

 opportunity of examining closely at the Museum. Unfortunately the 

 specimen was afterwards lost, owing to my own carelessness. It was 

 found with //. danicus and H. Mengii in the fern-house, and I hope that 

 local naturalists will pay special attention to the Trichoniscidae of the 

 Glasnevin Gardens, and again find this interesting form, so that it may 

 be described. 



It resembles T, linearis, Patience, superficially.but has each eye composed 

 of three visual elements instead of one. It is, moreover, exceptionally 

 narrow, being nearly live times the length of its greatest width. The 

 lateral parts of the segments of the mesosome are armed with a few (five) 

 very strong, downwardly curved spines. The extreme length of the 

 body, the linear form, the shape of the terminal expansion of mesosome; 

 which closely approaches that in T. linearis, and the prominence ami 

 number of the spines found on the lateral edge of each segment of the 

 mesosome at ouce separate the species from T^ pygin<eus. 



The colour is white, semi-pellucid, and with ramifications of minium- 

 red across the segments, similar to the coloration of the male of T. 

 linearis. The specimen seemed to me to be sexually mature. 



[' See notes on pp. 54-5 of this number.— Ed.s,] 



