On new Species of Marmosa. 519 
After the death of the bee the mites continue to live for 
several days, and the great majority of them seem to die 
finally without leaving the body of the host. Occasionally a 
few adult mites may be found moving about on the dead 
bodies of the bees. Whilst dissecting some healthy hive-bees 
from Golder’s Green, I found a single specimen of a male 
Tarsonemus (sensu stricto) in one of the thoracic tracheee— 
so that more than one species of mite of this family can gain 
access to the respiratory system of the bee. I have also 
found specimens of Tursonemus (s. s.) on dry specimens of 
Apis dorsata and Apis florealis (both Indian species of bees) 
and on Apis mellifica, var. indica (from Singapore). 
LX.— Three new Species of Marmosa, with a Note on 
Dideiphys waterlousei, Tomes. By OLDFIELD ‘l'HOMAS. 
(Published by permission of the Trustees of the British Museum.) 
In 1917 Dr. Carlos Bruch, Director of the La Plata Museum, 
published * a charming little account of the habits and nests 
of the Comadrejitas—the small Marmosas—of Argentina, 
and mentioned specimens of this group which he had obtained 
in San Luis. ‘These specimens he has now sent me for 
determination, and I find that they represent a very distinct 
species, decidedly smaller than any hitherto known from 
Argentina. I propose to name it, in honour of its discoverer, 
Marmosa bruchi, sp. n. 
A very small species of the MW. marmota group. 
Size exceedingly small, the smallest of the genus; just a 
shade smaller than the Para MW. emilie, the feet much 
smaller. General pattern of coloration as in marmota and 
citella, but the colour itself very pale, though this may have 
been slightly affected by the action of alcohol. Dorsal area 
rather greyer than “ drab”; intermediate lateral area “ light 
drab” ; under surface pure sharply defined white. Face 
without marked dark patches, the actual eyelids alone 
brown ; outside these the area round the eyes whitish. Hars 
large—no prominent white patches round their bases. Limbs 
white, the body-colour scarcely encroaching at all upon them. 
Tail of medium length, slightly incrassated, hairy at base 
only, drab above, whitish below. 
Skull lightly built, of normal shape. Nasals_ slightly 
* Revist. Jard. Zool. Buenos Aires, December 1917, no, 52, 
