212 



ANNALS OF SCOTTISH NATURAL HISTORY 



SKVE (continued}. 



EIGG (continued). 



H. nigrita, F, 



A. congener, Payk. 



A. arcticus, Payk. 



Rh. exoletus, Forst. 



G. minutus, F. 



H. picicrus, Thorns, 



L. minutus, L. 



L. truncatellus, Thuni>. 



H. confinis, Steph. \ 



C. insequalis, F. 



D. latus, Steph. 



D. assimilis, Payk. 



1 D. elegans, Pans. 



D. i2-pustulatus, Ol. 



D. griseostriatus, Zte G. 



H. lepidus, (97. 



H. palustris, L. } 



H. incognitus, Sharp. 



A. chalconotus, /* 



P. maculatus, L. 



I. cenescens, Thorns. 



D. punctulatus, .# 



D. lapponicus, Gyll. 



G. opacus, Sahib. 



H. aquaticus, Z. 



per cent. 



per cent. 



8 



D. lapponicus, Gyll, \ 



H. brevipalpis, Bedel. / 



H. rivalis, 



H. morio, 



I. fuliginosus, / 



D. punctulatus, 



D. assimilis, Payk. 



H. celatus, Clark. 



H. melanarius, Sturm. 



H. discretus, Fairm. 



H. lituratus, ^". 



I. senescens, Thorns. 



G. minutus, /; 



H. fuscipes, Z. 



H. picicrus, Thorns. 



Ph. minutus, /^ 



P. nigroaeneus, Sahib. 



A. limbata, ^ 



C. orbiculare, F, 



O. lejolisii, Rey and 

 only occurred in brackish water- 

 pools on the rocks, and I have 

 not counted this or L. Tighe in 

 the above 33 collections. 



Now although all the species high in these two lists are 

 oxylophiles (or species such as A. bipustulatus which are 

 equally at home as halophiles, helophiles, etc.), some of 

 those far down are also undoubtedly oxylophiles, and their 

 lowness is, of course, due to their rarity. It is not easy to 

 account for the rarity of some of these species, as for 

 example : A. congener, A. cJialconotus, I. cenescens. Some, 

 such as P. nigrocsneuSy are evidently at the northern limit of 

 their range, while in the case of certain others some remarks 

 may be of interest. 



The oxylophile group is not a simple association 



1 Through correspondence and exchange of specimens with M. Sainte Claire 

 Deville I find that all my Britannic specimens recorded as D. depressus, F. , are 

 in reality D. elegans, Panz. D. depressus is an arctic species and may occur in 

 Scotland or the North of Ireland, but I expect that all the specimens in our 

 collections under this name are Panzer's species. It is surprising that such a 

 mistake should ever have got into our catalogues. 



