54 SUBAXTARCTIC ISLAXDS OF NEW ZEALAND. [MoUmca. 



SUMMARY. 



The result of the scientific expedition to the subantarctic islands of New Zealand 

 is, as far as Mollusca are concerned, very satisfactory, especially when considering 

 the fact that no conchologist accompanied the expedition. Of special interest and 

 great importance is the discovery of new non- marine species of Mollusca, which 

 number 6, and the marine 4. 



The total of the genera now known to occur, and enumerated, amounts to 105, 

 and the number of species and varieties to 208, which is certainly more than one 

 would expect in these latitudes. A great number of these are also met with in New 

 Zealand, some in Tasmania and Australia, and only a small number are circumaustral 

 or partly so. 



Leaving out the small forms dredged near the Snares and Bounty Islands, the 

 following twenty-eight species may be mentioned as being precinctive to our sub- 

 antarctic islands, as far as our present knowledge goes : — 



Ischnochiton farkeri. Therasia eifeditionis. 



Mopalia australis. ,, antifoda. 



Plnxiphora aucklnndica. Phenacohelix suhantarctica. 



„ superba. Ranfurhja constanceae. 



Acmaea intermedia. Endodonta benhwni. 



,, campbelli. ,. minuta. 



Nacella illuminata. Laoma campbellica. 



Cantharus pruninus. ., cognata. 



Calliostoina aucklandicum. Athoracophorus huttoni. 



Laevilitorina antipodum. „ martensi. 



Turritella difficilis. „ verrucosus. 



Eidima aucklandica. Onchidella cfimpbelli. 



ComineUa campbelli. Arcfi aucklandica. 



Thermia expeditionis. Polypus camphdli. 



More or less circumaustral are the following nine species : — 



Callochiton puniceus. Mytilus mageUanicus. 



Nacella fuegiensis. Modiolarca pusilla. 



Monodonta nigerrima. Chione stutchburyi. 



Argobuccinum argus. ,, mesodesma. 



Siphonaria lateralis. 



Another circumaustral species is Laevilitorina caliginosa, Gould, which has been 

 found at Macquarie Island, but seems to be absent or not yet found on the islands 

 to the north-east. 



It is very interesting to see Doris {Ctenodoris) flnhellifera turning up at tlie 

 Snares, the species having been known only from Auckland Harbour. 



A former land connection between New Zealand and the subantarctic islands 

 seems to be proved by the occurrence in the islands of Allodiscus planulatus, Flatn- 

 mulina phlogophora, Endodonta anguiculus, Sphaerium novae-zdandiae, and also of 

 the genus Athoracophorus. Athoracophorus huttoni is found on the Snares and on 

 Macquarie Island ; A. martensi lives on the Auckland Islands and on Macquarie Island, 

 which also suggests a former land communication between the respective islands. 



