-^50 On British Land Isopoda. 



liowever, to BudJe-Lund we find the flagellum of bis Triclio- 

 niscus a/i«'o^«<s described as ^' bi—triarticulatian.^^ Tbe species 

 was previously known only in Norway and Ddnmark, and is 

 an addition to our fauna. 



PorceUio Rathkei^ Brandt. 



1833. PorceUio Hathket, Brandt, Conspectus Monogr. Crust. Isop. 



terrest. p. 15. 

 1853. PorceUio trivitfMus, Lereboullet, M^m. Crust. Fam. Cloportides, 



p. 54, pi. i. tigs. 13, 14, pi. iii. figs. 66-70. 

 1885. PorceUio Rathkei, Budde-Lund, Crust. Isop. terrest. p. 85. 

 1898. PorceUio Rathkei, G. 0. Sars, Crust, of Norway, vol. ii. Isopoda, 



p. 180, pi. Ixxix. fig. 1. 



A single adult specimen taken by G. S. B. at Humbledon 

 Hill, near Sunderland ; new to the British fauna. P. Rathkei 

 has a range over the greater part of the northern portion of 

 the Continent of Europe, and is known as far east as Trans- 

 caucasia. It has been found also in N. America, near New 

 York and near Niagara. 



Other synonyms of this species are P. ferrugineus, Brandt, 

 P. trilineatus, P. tetramcerus and striatus^ Schnitzer, P. 

 sijlvestris, Schobl. 



Armadillidium joulchellum (Zencker). 



This Armadillidium, which was added to the British fauna 

 by Dr. Scharff, who found it at Sligo, has this year been 

 obtained by G. S. B. at Arnside, Westmorland. 



In the paper referred to at the commencement of these notes 

 as published in 1899, a list was given of all Land Isopoda 

 found in the northern countries of Europe ; the number 

 occurring in each country was as follows : — Norway, 17 ; 

 Sweden, 13 ; Denmark, 20 ; Holland, 11 ; Belgium, 17 ; 

 British Isles, 20. This last number has now been raised to 

 25. The only species which are found in the other northern 

 countries, but as yet are not known in ours, are Trichoniscus 

 pygmceus, G. O. Sars (Norway) ; Armadillidium pictumj 

 Brandt (Sweden, Norway, Denmark, and Belgium) ; Arma- 

 dillidium opacum, Koch (Denmark) ; and Armadillidium 

 sulcatum, M.-Edw. (Belgium). 



Two of the British species, Armadillidium wasM^wm, Budde- 

 Lund, and^. depressum, Brandt, have not yet been met with 

 in any of the countries above mentioned. 



From the species which have been found in the neighbour- 

 hood of Sunderland, as recorded in the foregoing notes, it 

 would seem as if the Magnesian Limestone of the district 

 was favourable to the life of Land Isopoda. 



