Report on the zoological collections made in the Indo-Pacific Ocean ...

;MOLLUSC A.Cryptoplax striata, frunnii, rostrata, Adams, Genera,Angas, Proc. Zool. Sue. 18G7, pp. 224, 225.85vol. i. p. 434'-T^tk T?QiTi£»a Tala-nrl HPrwroc ftfvoifc / 7?/j/?irz3Hab. Raines Island, Torres Straits (Beeve, fnT* for f) C. rostratus andC. striatus), Port Lincoln (J. B. Harvey), Newcastle {Dr. Dieffenbach),Port Jackson {Coppinger, Richardson, Juhes, King)— all inBrit. Mus. ; Hinders Island (./. MilJigan) ; Tasmania {Reeve,C. gunnii) ; Tasmania {Mucgillivray and Gunn, in Brit. Mus.).The variety gunnii, from South Australia and Tasmania, may berecognized by the valves being narrower, with the exception of thefirst two. This form also appears to attain a larger size than specimensfrom New South Wales and other localities further north. Aspecimen in spirit, from the mouth of the river Tamar, Tasmania,presented to the British Museiim by J. Macgillivray, exceeds fourinches in length. The mantle of the southern form also appears tobe rather less densely covered with the minute conical spines. Thenumber of gills on each side varies with age, and even in individualspecimens : I have found 30 or 31 on each side in specimens ofequal size from both regions— that is, north and south ; and in thelargest specimen before referred to there are 37 on the right sideand 34 on the left, and there is no appearance of any having beenremoved. The plates of insertion offer no distinctions, each havingthree slits in the front valve and none in the rest, as is the case inall Chitonelli. The colour both of the valves and mantle seems toagree very closely in all the varieties, The 0. rostratus of ReeveI cannot in any way distinguish from the shells figured by him asLamarck's C. striatus, and the same observation also applies to hisnotion of Quoy's 0. oculatus. What the latter may in reality be isan uncertainty to me at present, for I cannot identify any specimenin the British Museum with it.119. CMton (Chitonellus) burrowi.Chitonellus larvseformis, Reeve {non Burrmv), Conch. Icon. fig. 3.Hab. Port Molle {Coppinger) ; Port Adelaide {Reeve).This curious species is known by the small size of the valves, theremoteness from one another of the fourth, fifth, and sixth, and theexcessively short and densely packed spines on the mantle. Thesingle specimen in spirit, from Port Molle, is of a buff colour,copiously mottled with green : this accords with a specimen (alsoin spirit) mentioned by Reeve, collected by Capt. Belcher in theStraits of Macassar.The dried specimens are greyish, more or less rose-tinted.The sculpture of the valves is very like that of 0. striatus, consistingof a central smoothish ridge, with two or three finer and moreor less wrinkled ones on each side, the front valve of course beingwrinkled throughout and lacking the central smooth ridge. Theyare yellowish at the mucro or posteriorly, and pinkish red in front.The plates of insertion are like those of C. striatus, and of a palegreenish colour.