fossil cirripedes from new zealand. 841 



Balanid^. 

 Genus Hexelasma. 



1913, Hexelasma P. P. 0. Hoek, Siboga-Expeditie, Cirripedia 

 Sessilia, p. 244. 

 "Compartments six ; carina, carino-lateral, and lateral compart- 

 ments with alte, but without radii, the rostrum having neither 

 radii nor alse. Parietes not porose and without longitudinal 

 ribs on their inner surfaces ; basis membranous. Opercular 

 valves sub-triangular." .... P. P. C Hoek. 



Hexelasma aucklandicum Hector sp. (PI. LXXXV.) 



1888. Scalpellum aucklandicma Hector, Trans. N.Z. Institute, 



vol. XX. (1887) p. 440. 

 1903. Pollicipes ? wucklandicus Hector sp. : W. B. Benbam, " On 



some Remains of a Gigantic Fossil Cirripede from the 



Tertiary Rocks of New Zealand," Geol. Mag. London, 



dec. 4, vol. X. p. Ill, pis. 9, 10 {non figs. 8, 9). 

 1905, Pollicijns aucklanclicus Benham : E. Clarke, "The Fossils 



of the Waitemata and Papakura Series," Trans. N.Z. 



Institute, vol. xxxvii. (1904) p. 419, 

 1910. Pollicipes 1 aucklandicus Hector sp. : J. Park, "Geology 



of New Zealand," p. 115 (pi. 7), pp. 113, 134. 

 Diagnosis. Compartments attaining a length of at least 187 mm., 

 carina!, carino-lateral, and lateral compartments with simple alas 

 {i. e., there is no distinct upturned extension at the margin). 

 Sheath feebly developed, almost absent, and with no suturai edge 

 to abut against the longitudinal ridge formed on the inner 

 surface. Opercular valves unknown (except for probably a single 

 tergum). 



Material. 7 rostral compartments, 9 carinal, 13 lateral (8 right 

 and 5 left), 5 carino-lateral (3 right and 2 left), together with a 

 small tergum (PI. LXXXY. figs. 13«, h), which may or may not 

 belong to the species ; all these are more or less imperfect. The 

 specimens are in the collection of the Geol. Surv. New Zealand, 

 and are marked with the locality-number 695. They are pre- 

 sumably the syntypes of Hector. In addition to these specimens 

 I have examined plaster-casts of the specimens figured by 

 Prof. Benham. 



Holotype. Fi-om among the syntypes of Hector I select as 

 holotype the rostrum here figured on PI. LXXXV. fig. 1. 



Horizon and Locality. Miocene, Oamaruian, Base of Waitemata 

 Beds: Motutapu Island, Auckland Harbour, New Zealand. 



General Remarks. Sir James Hector (1887) first called at- 

 tention to this fossil, and at a meeting of the Wellington 

 Philosophical Institute he remarked on some remains of it there 

 ■exhibited : — 



" Specimens of a large fossil stalked Cirripede, recently 



