CANARIAN GROUP. 419 



muros rupesque hinc inde adhserens. In Canaria Grandi etiam 

 sertiifossilis reperitur. 



A common, though variable, Bullmus at low elevations in 

 Teneriffe and Palma, and (under a tolerably well marked aspect) 

 at higher ones in Lanzarote, and one which has been found by 

 Mr. Watson in Grrand Canary likewise. It may be said to 

 differ, in a general way, from the B. tnyosotis of the last-men- 

 tioned island (if indeed the myosotis be anything more than a 

 mere elongated and concolorous modification of the variatus 

 characteristic of Grrand Canary) in being a little less solid in 

 substance and less slender (or more ovate) in outline, — the last 

 two or three whorls being relatively a trifle more shortened ; 

 and it is also usually less opake, and of a less uniformly pale (or 

 yellowish) brown, — the unmaculated state (' a. riifobriinneus ') 

 from Lanzarote being of a rich coffee-colour, and the smaller 

 and more or less maculated one from Grand Canary and Tene- 

 riffe (which, like Mousson, I have regarded as the type), 

 although occasionally of a pallid brunneo-olivaceous tint, being 

 at the same time more or less marbled with obscure, longitudinal, 

 oblique, irregular fragmentary lines and streaks of a rather 

 lighter hue. The ' 8. siihgracilior^ from Palma, has certainly 

 the slenderer form and rather elongated volutions of the B. 

 "tnyosotis ; but, on the other hand, its features of comparative 

 thinness and brightness are even more expressed than in the 

 ' 7.' or normal state of the species, — thus affiliating it with the 

 B. variatus, rather than with the B. myosotis from Grand 

 Canary. 



Judging from two original examples which are now in the 

 British Museum, the B. roccellicola, W. et B., is certainly 

 nothing more than a variety (if indeed a true 'variety' at all) 

 of the B. variatus, — differing far less from the ordinary Tene- 

 rififan and Grand-Canarian type than the ' status a. rufobrun- 

 neus ' does, which is the common form in Lanzarote, It is 

 perhaps a trifle more ovate, and (if anything) a little smaller, 

 than the normal phasis of the shell ; and its surface is of a 

 palish brown, — in one of the specimens quite concolorous, and 

 in the other just appreciably mottled with a few irregular frag- 

 mentary thread-like lines. After examining these two indi- 

 viduals with great care, I can perceive absolutely nothing about 

 them to warrant specific separation, — their distinctions, such as 

 they are, being scarcely even varietal. 



The Lanzarotan phasis of this shell, which I cannot but 

 think has quite as great a claim for specific separation as is 

 possessed by the Graud-Canarian B. myosotis, occurs on the sub- 

 maritime rocks of a rather high altitude, — it having been found 

 in abundance by Mr. Lowe and myself on the lofty sea-clififs 



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