230 Records of the Indian Museum. [Vol. VI, 1911.] 



which Lanchester (P. Z. 5., 1902 (i), p. 372) recorded from Pulau 

 Bidan near Penang as L. quadrivalvis. The specimens from Port 

 Jackson and New Zealand clearly represent the true /. quadrival- 

 vis and are hermaphrodite. This form was not taken in the Malay 

 Archipelago by the ' ' Siboga. ' ' 



Taking these facts into consideration, I am inclined to believe 

 that /. quadrivalvis and /. cummingi are merel}?- local races, the 

 one confined to the southern part of the Pacific, Madagascar and 

 the east coast of Africa, the other to the waters of the Oriental 

 Region and the Persian Gulf ; and that all records of /. quadrivalvis 

 from the Oriental Region refer actually to /. cummingi var. sibo- 

 gae, which occurs on the coast of Burma, in the Straits of Malacca, 

 the Gulf of Siam, the Malay Archipelago and also at Muscat in 

 Arabia. 



Neither the variety sibogae nor the typical form of /. cum- 

 mingi is invariably associated with Pollicipes as was the case with 

 Darwin's specimens of the latter from the Philippines— he does not 

 state that it was the case with those he examined from Lower 

 Burma. Capt. F. H. Stewart took numerous specimens of both 

 forms on an island off the coast of Burma {Mem. Ind. Mus., iii, p. 

 36), but no specimens of Pollicipes ; while the specimens of the 

 latter genus taken by Dr. W. Mortensen in the Gulf of Siam do 

 not appear to have been found on the same date as those of Ibla 

 from the same locality {Sacr. Vid. Medd. naturh. Foren. Koben- 

 havn, 1910, pp. 81, 85). The sexual peculiarities of /. cummingi 

 cannot therefore be correlated with a semi-parasitic mode of life, 

 although they may possibly be due to climatic influences. Before 

 theorizing on this point, however, it might be well to check the 

 records of the different forms of the genus, and I would appeal to 

 all students of the Cirripedia who have the opportunity of examin- 

 ing specimens of Ibla (or of an\^ other genus) not to trust merely 

 to an external examination of the shell in their determination of 

 the species but to dissect the animal out before recording its name. 



N. Annandalk. 



