CRUSTACEANS 



impracticable task. Dr. Sorby reports the curious parasitic copepod, 

 Lerneonema spratta (Sowerby), 'found on the eyes of sprats caught in 

 the open water off Essex,' and the sessile cirripede ' Balanus punctatus ' 

 as ' common all along the coast, and especially in the estuaries, where 

 the number of larvae is sometimes so great that in a few days the bottom 

 of a yacht is completely covered with the young shells.' In regard to 

 ' B. punctatus ' a reference to Darwin's celebrated work shows that the 

 name is rather deeply afflicted by chronic vagueness. Under his account 

 of B. balanoides (Linn.) Darwin explains that this species, 'in its corroded 

 and therefore punctured state, is certainly the B. punctatus of most British 

 collections ; but,' he adds, ' I do not believe it is the B. punctatus of 

 Montagu, which I have scarcely any doubt is the Chthamalus stellatus so 

 often found in the southern shores of England, and even in some of the 

 best arranged collections, mingled with our present species.' 1 Under 

 C. stellatus (Poli) he says, ' On the coast-rocks of the southern shores of 

 England it is, in parts, even more numerous than the Ba/anus balanoides, 

 with which it often grows mingled. As already stated, it is often con- 

 founded in British collections with this species of Balanus under the 

 name of B. punctatus \ that Montagu had this Chthamalus in view when 

 describing his Lepas punctatus is certain, from his original specimen in 

 the British Museum, but whether this was the case with his predecessor 

 Pulteney in the Dorset Catalogue 1 do not feel so sure.' 1 As Dr. Sorby 

 has kindly furnished me with some of his specimens, I can testify that 

 they include Chthamalus stellatus, and, as I believe, also Balanus crenatus, 

 Bruguiere, which has a calcareous basis, whereas that of B. balanoides is 

 membranous. On the whole it may be concluded that there are at 

 least three species of Thyrostraca or Cirripcdes on the Essex coast. 

 Apart however from Dr. Sorby's interesting manuscript notes, the 

 crustacean parasites of fishes and of many other aquatic animals, the 

 barnacles, stalked or sessile, fixed or floating, and several important 

 groups of the Malacostraca have hitherto had few records or none by 

 which their relative prominence in this locality can be determined. 

 Some future faunistic description of Essex will show, certainly that they 

 are not absent, probably that they are present in abundance. 



1 Balmidae, Ray Soc. pp. 208, 456 (1854). 



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