AVICULA. 97 



vessels are bound. Miss Hutchings, who (according to 

 the late Mr. James Sowerby) discovered this species in 

 Bantry Bay, was infinitely better acquainted with sea- 

 weeds than with shells. I have some of the latter which 

 Mr. Dillwyn received from that lady, as collected by her 

 in Bantry Bay, and which are unquestionably Mediter- 

 ranean and not Irish. One of them is Area barbata. 

 Such mistakes often happen in spite of the best inten- 

 tions. I do not say, however, that A. hirundo has never 

 been found in Ireland, or that it may not hereafter be 

 rediscovered there. It occurs, but very rarely, in the 

 Coralline Crag. Its exotic distribution is wide, and 

 comprises both sides of the Mediterranean, as well as 

 the Adriatic and iEgean Seas, the Canary Isles, Madeira, 

 and the Azores. Mr. M 'Andrew has taken it on the 

 shore near Gibraltar, and in the Canaries as deep as 50 

 fathoms. 



The shell has a very remarkable shape, not unlike 

 that of a swallow on the wing. Two of Lamarck's 

 species of Avicula (Atlantica and Tarentind) appear to 

 be the same as the present species, representing the 

 younger and mature states of growth. The former he 

 describes as having the valves unequal in size, and the 

 latter as being equal- valved. If one of these specific 

 names had to be selected, the description of "Atlan- 

 tica " would therefore be more appropriate than that of 

 " Tarentina M to our shell. Linne's diagnosis of Mytilus 

 hirundo is equally applicable ; and it would be a pity to 

 reject that time-honoured name in favour of any other 

 given by subsequent writers. Turton was mistaken 

 when he described, in his f Conchological Dictionary/ a 

 second species {A. morio) as British, on the authority of 

 Dr. Leach. The latter distinctly stated that species to 

 be exotic; but in his account of the genus Avicida 



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