34 NATURAL HISTORY ESSAYS 



Were it not for the rarity of the jumping shrews 

 one might suggest that the resemblance conversely 

 benefits the jerboas also; for like many insectivores 

 the macroscelides exhales a musky odour which may 

 render it distasteful to its enemies. A young hawk 

 or owl that had in its inexperience seized a nauseous 

 shrew might afterwards {having once learnt a lesson) 

 unwittingly spare a toothsome jerboa. One cites in 

 support of this theory the reversed mimicry of 

 insectivore by rodent seen in the tupaia-like squirrels 

 of Burmah, Borneo, and Sumatra.^ Such analogies 

 must not, however, be pressed too far. In cases 

 of undoubted mimicry it is always the luiinicked 

 species which is abundant, which would not be the 

 case with a jerboa copying a shrew. Besides, the 

 musky odour of the common English shrew "mouse" 

 does not prevent it from being killed by dogs and 

 cats. 



Sparingly distributed throughout North-Western 

 Africa, the elephant shrew is nowhere common. 

 M. Parzudaki's collection contained two examples 

 taken in Oran and afterwards acquired by the British 

 Museum. Canon Tristram in i860 recorded it from 



1 On tlie same day (February 8tli, 1875) there arrived at the London 

 Zooloffical Gardens two curious animals, both new to the collection. 

 Tliey were a tree slirew {Tujwui pctjiiiina) presented by tiie Hon. Ashley 

 Eden, C.S.I., of Rangoon, British Burmah, and a Blandfords sijuirrel 

 {^ciurus blandfurdi) presented by Mrs, Dunn. These were placed in 

 the same cage, the scjuinel e.xliibiting a marvellous resemblance to the 

 tupaia. Perhaps this was a case of true mimicry. The tree shrew was 

 believed to lie the first tupaia of any species to reach Europe alive. 

 Another instance of mimicry is seen in Everett's s<iuirrel {S'-im-us 

 evcrcfti), of Borneo, which resembles the mountain tupaia {T. montana). 



