Zoological Society. 135 



Mus Nov^-HoLLANDi^. Mus suprtl canus flavescente-lavatus ; 

 corpore subtils pedibusque albis ; auribus mediocribus ; caudd quoad 

 longitudinem corpus fere cequanfe. 



unc. lin. 

 Longitudo ab apice rostri ad caudse basin. ... 3 



caudee, circiter 2 



tarsi digitoru7nque 9j 



Hub. New South Wales. 



This mouse was found, together with two young specimens, under 

 a large slab of bark at Yarrundi, Upper Hunter, New South Wales. 

 In size and colouring it approaches most nearly to the Mus sylvaticus, 

 but its tail is considerably shorter than in that animal. In the form 

 of the skull the present species also approaches the M. sylvaticus, 

 but the nasal portion of the cranium is shorter ; the molar teeth are 

 of the same structure, but apparently rather larger in proportion. 

 The fur is rather long and very soft ; on the upper parts the hairs 

 are of a deep grey colour, tipped with brownish yellow ; on the belly 

 the hairs are of a less deep grey colour next the skin, and white ex- 

 ternally. The tarsi are rather long and slender. The tail is white 

 beneath and dusky above, 



November 8. — R. C. Griffith, Esq., in the Chair. 

 An extract of a letter from the Society's President, the Earl of 

 Derby, was read. His Lordship observes, with reference to some 

 young Rheas hatched in the menagerie, that the eggs were laid in 

 one of his Lordship's paddocks, and were collected into a nest by the 

 male bird, Avho sat upon them very perseveringly until the keeper, 

 thinking the spot selected was too exposed, removed the eggs and 

 l)laced them under some Turkeys. They were ultimately, however, 

 placed in Mr. Appleyard's hatching apparatus, and in about a week 

 or ten days were hatched. The letter moreover announces the safe 

 arrival of three Elands (Antilope Oreas, Pall.) in his Lordship's me- 

 nagerie. 



A memoir on the anatomy of a species of Calyptraa with a ven- 

 tral shelly valve (Lithedaphus longirostris, Ow.), by Prof. Owen, was 

 then read. The normal valve secreted by the Lithedaphus resembles 

 a Calyptrcea, and indeed is possibly a variety of the Calyptrcca 

 equestris of authors ; but the animal is inclosed, like the Acepha- 

 lous MoUusks, in a bivalve shell. The additional plate, in the 

 present instance. Professor Owen shows to be connected with a mo- 

 dification in the organization of the animal which establishes its 

 claim to a subgeneric distinction among the Calyptrceidce. The 

 specimens dissected were collected by H. Cuming, Esq. in the Phi- 

 lippine Islands, and the circumstances connected with this discovery 

 are recorded by that gentleman in the ' Conchologia Systematica' of 

 Mr. L. Reeve (vol. ii. p. 31). 



" Lithedaphus differs from all previously described Calyptrceidcs in 

 some well-marked external characters of its soft parts. The head, 

 instead of being short, broad and flat, is long and subcylindrical ; 



