ZOOLOGY AND BOTANY, MICROSCOPY^ ETC, 43 



Natural History of Haliotis.* — H.Wegmann has published in 

 full the essay of which a preliminary notice has already appeared, 

 and which has been noted in this Journal.j The following points 

 may now be noticed : — The digestive organs attain a high grade of 

 differentiation, and are divided into a series of very distinct parts, 

 and they occupy the greater part of the abdominal cavity ; there are 

 two pairs of buccal cartilages, whereas most Gastropods have only 

 one pair, and Patella has three (Geddes). The author, by the way, 

 defends the use of the term fibro-cartilage, to which exception has 

 been taken by Lebert. The " saliva " is whitish in colour, and mucous 

 in consistency ; the " liver " is enormous, and is essentially divided into 

 a right and left lobe. The author discusses the function of the rudi- 

 mentary gills, which he allows to be the same as the organ to which 

 notice was directed by Spengel, and which sometimes bears his name ; 

 but he doubts whether the generally accepted view that the part in 

 question has a sensory function is correct ; he does not find that it is 

 any richer in nerves than tlie true gill, and he is inclined to look 

 upon them as being a pair of rudimentary branchiae. 



* Challenger ' Nudibranchs.t — Dr. E. Bergh reports on the 

 Nudibranchs of the ' Challenger ' expedition. As few shallow-water 

 dredgings were made during the cruise, it is not to be wondered at 

 that the number of Nudibranchs collected was but twenty-five, in- 

 cluding only one deep-sea form. 



The majority of the forms belonging to the Phylliroidee and 

 iEolidiadse which were collected are pelagic, and are represented by 

 the genera PJiylliroe, Glaums, Fiona, &c. ; some are littoral, such as 

 Janolus australis, a single specimen of which was taken in the 

 Arafura Sea, and one like the last referred to a new genus and 

 species, Cuthonella ahyssicola, was taken in the Faroe Channel from a 

 depth of 608 fathoms. Several new species belonging to the Tri- 

 toniadee are described. Of the Dorididge, two new genera and several 

 new species were diagnosed. Of these the most interesting is Baihy- 

 doris abyssorum. This differs from all others of the family in the 

 semi-globular form of the body, which is somewhat like that belonging 

 to the genus Kalinga of Alder and Hancock, and which it also 

 resembles in the characters of its branchia, these being composed of 

 several separate branchial tufts, also in the development of soft conical 

 papillae upon the back. It has no frontal appendage, and the dorsal 

 margin is very slightly pronounced. This new genus would appear to 

 form a remarkable connecting link between the Tritoniadse and the 

 Dorididae. The only specimen found was taken from a depth of 

 2425 fathoms, in the middle of the Pacific. 



In an appendix. Dr. Bergh describes the only Onchidium in the 

 collection as O. melanopneumon. Only one specimen was taken in 

 shallow water, at Kandara, Fiji. For comparison with the new species 

 details of the anatomy of 0. tonganum and 0. verruciilatum are given. 



* Arch. Zool. Exper. et Gen., ii. (1884) pp. 289-378 (5 pis.). 

 + See this Journal, iv. (1884) p. 730. 



t Report of the Voyage of H.M.S. 'Challenger,' Zoology, x. (1884) 154 pp. 

 (14 pis,). See Nature, xxxi. (1884) p. 165. 



