380 Dr. C. Chilton on 



XLIII. — The Species of Limnorla, a Genus of Wood-boring 

 Isopoda. By Chas. Chilton, M.A., D.Sc, LL.D., 

 M.B., CM., F.L.S., Professor of Biology, Canterbury 

 College, N.Z. 



[Plate XVII.] 



On July 29tli, 1913, 1 received from the autliorities of the 

 Auckland Harbour Board a piece of timber that was being 

 destroyed by a marine borer, witli the request that I would 

 see if the borer was the "gribble," Limnoria lignorum, 

 Rathke. An examination at once showed that the borer 

 was certainly a species of Limyioria ; the decision as to 

 whether it was the European species or not required some 

 care, as in 1883 * I had described from Lyttelton Harbour, 

 New Zealand, another species, Limnoria segnis, which in 

 general appearance was extremely like L. lignorum^ though 

 differing from it in the characters of some of the mouth- 

 parts and living on seaweed instead of boring into wood, 

 A detailed examination and a comparison with specimens 

 from Plymouth, England, showed, however, that tlie animal 

 boring into the wood in Auckland Harbour was indeed 

 L. lignorum. This conclusion, moreover, was confirmed by 

 the fact that, accompanying the Limnoria, there were also 

 some specimens of an Amphipodan borer, which, on com- 

 parison with specimens from Plymouth, England, proved to 

 to be identical with Chelura terebrans^ Pliilippi, a species 

 associated with Limnoria lignorum in Europe f. These two 

 species must evidently have been introduced into New 

 Zealand, probably in some old wooden vessel, and they thus 

 afford an example of the accidental dispersal of marine 

 Crustacea by means of ships, additional to those already 

 recorded by me (1911, p. 131). 



It cannot be ascertained for certain how long ago these 

 two Crustacea were introduced into Auckland Harbour, but 

 in all probability it was many years' ago. They appear to 

 find the locality favourable, for they were extremely numerous 

 in the samples of wood that were sent down to me, and they 

 seem to be causing rapid destruction, both of the softer 

 timbers, such as Kauri, and even of harder kinds, such as 

 Totara. 



* The references are made by the year of publication to the list at the 

 end of the paper. 



t It should be romeuibered that at Christmas Island, Indian Ocean, 

 another species, Limnoria andrnvsi, is associated -with a diH'ereut species 

 of Chelura, i. e. C. inmla, Caiman (see Caiman, 1010, p. I8i'). 



