144 The Naturalist of Cumbrae. 



but his visits to the shores and waters of Cumbrae, 

 though they might be short, were frequent, and his 

 diary shows that he was continually searching for the 

 treasures of the sea shells and weeds, crabs and 

 shrimps and other crustaceans of various orders, 

 annelids and sea-anemones, starfishes and sea-urchins, 

 hydroid zoophytes, naked mollusks, and fishes. 



His skill and acquisitions became known, and 

 he entered into correspondence, in regard to sea- 

 anemones, with the late popular zoologist, P. H. 

 Gosse. On sessile-eyed Crustacea he corresponded 

 with I. O. Westwood, the celebrated entomologist, a 

 still living and actively-working veteran ; and also 

 with the late Charles Spence Bate, to whom he sent 

 many specimens of great interest for description in 

 the work which he was then preparing in conjunction 

 with Professor Westwood. 



In 1857, Mr. Robertson obtained a specimen of the 

 curious little fish, Amphioxus lanceolatus, to which 

 reference will again be made in another chapter. 

 Eager demands were made upon him by naturalists 

 for specimens of this interesting animal. 



His researches were not confined to aquatic objects. 

 He did not neglect the ferns or the mosses. But he 

 was also, at this period, turning his attention to a 

 very abstruse subject, in which land and water were 

 almost equally concerned, for, about the year 1855, 

 he joined the Rev. H. W. Crosskey in what proved 

 to be a very long and laborious task the preparation 

 of a paper on the post-tertiary deposits of Scotland. 



For the benefit of the few who are not students of 

 geology, it may be observed that the fossil-bearing 



