178 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Boring Cirripedia.* — W. Berndt proposes a revised classification of 

 the Acrothoracica, or boring Cirripedia. The sub-order Pygophora in- 

 cludes the family Cryptophialidae (Cryptophialus) and the family Koch- 

 lorinidse (Kochlorine, Lithoglyptus, and Weltneria). The sub-order 

 Apygophora includes the family Alcippidas (Alcippe). 



Barnacles of the United States National Museum, f — Henry A. 

 Pilsbry gives an account of the pedunculate Cirripedes and the sessile 

 family Verrucidae in the United States National Museum. He deals 

 with the following- genera : — Mitella, Lithotrya, Scalpellum, Oxynaspis, 

 Dpus, Pacilasma, Megalasma, Octolasmis, Gonchoderma, Heteralepas, 

 Alepas, and Verruca. The Pedunculata from North American coasts 

 number 56 species, and the Verrucidse 5 species. The pelagic forms, 

 with one exception, are widely distributed forms, already known from 

 many Atlantic and Pacific localities. One pelagic species, Alepas 

 pacifica, is an interesting form commensal on large medusa?. The deep- 

 water forms, both of Lepadida? and Verrucidse, support the opinion 

 advanced by Hoek, Annandale, and others, that deep-sea Cirripedes have 

 ■a very wide distribution. 



Notes on Cirripedes. — Henry A. Pilsbry % describes some new 

 Japanese and North-Western Pacific Cirripedes — Scalpellum g 'onion otum, 

 S. weltnerianum, and Balanus orcutti. 



In another paper, Pilsbry § discusses the genus Megalasma, which is 

 distinguished from Paicilasma by the structure of the carina, which has 

 wide sides near the base, and a well-developed oblique plate or septum 

 within the base, bridging across the cavity of the carina, and terminating 

 above in two projections or teeth. The species of Pacilasma occur 

 chiefly on the carapaces of crabs, while Megalasma has been found 

 mainly on sea-urchin spines and on other Cirripedes. A key to the 

 various species is given. 



North American Species of Diaptomus. || — C. Dwight Mason has 

 made a useful revision of the North American species of this cosmopolitan 

 genus, which is so prominently represented in fresh-water plankton. 

 All the North American species (34) are peculiar to the country, and 

 some have a relatively restricted habitat. Isolation has probably had 

 an important role in the evolution of the species, and it seems likely 

 that Diaptomus is very susceptible to environmental stimuli. Peculiar 

 bizarre characters are more apt to appear in species living in shallow 

 waters, and with a narrow range of habitat. There is a marked 

 distinction between deep-water and shallow-water species. There is no 

 reason to think that, under ordinary circumstances, the species are 

 distributed in any way except by water carriage. Various groups of 

 species — oreyonensis, teni/icaudatus, leptopus, signicauda, and albuqi'er- 

 quensis — are distinguished, and a systematic description is given of 

 all the species. 



* Arch. Natur., lxxiii. (1907) pp. 287-9. 



t U.S. Nat. Museum, Bull. No. 60 (1907) x. and 122 pp. 11 pis. and 36 figs.). 



J Proc. Acad. Nat. Sci. Philadelphia, 1907, pp. 360-2. 



§ Tom. cit., pp. 408-16 (1 pi. and 7 figs.). 



|| Trans. Wisconsin Acad. Sci., xv. (1907) pp. 381-516 (14 pis.). 



