THE GIANT FLEA : HYSTRICHOPSYLLA TALPAE. 257 



he has little doubt that the great numbers of specimens he had himself 

 observed on the cliffs belonged to the swarm that his daughter had 

 seen arrive that morning. 



The habit which butterflies have in calm weather of settling on the 

 sea when migrating, has been observed by many entomologists. 

 Pocklington records [Entom., vi., p. 152) that in May, 1872, he 

 watched several Ficris brasskac flying far from the shore in Boston 

 Deeps (Wash), and observed one of them apparently fall in the sea, 

 when, to his surprise, as the wave arose upon which it had alighted, 

 the butterfly mounted with it and flew away uninjured and apparently 

 refreshed by its resting there. The habit is important, as helping to 

 explain the physical ability of certain species to travel Avhat would 

 otherwise appear to be almost impossible distances. A too frequent 

 resting, however, would appear to be fatal, for it has been recorded 

 more than once that, when thus resting, although they are able to 

 rise a few times with ease, yet the scales soon get wet and then the 

 insect has some difficulty in rising again, and when the power fails it 

 necessarily perishes. We have already detailed {siqnrt) occurrences 

 when large numbers of lepidoptera have come to grief on one of 

 their voyages, but this must not be taken as in any way disproving 

 the general fact of their ability to rest on the surface of the 

 water. This failure has been noted in such strong-winged 

 species as Anosia arcMppu>i, Pijrameis cardni and others, and it 

 is probable that the attempt to rest once too often is sometimes the 

 cause of the large number of dead lepidopterous insects which are 

 occasionally observed floating on the surface of the water at various 

 times and in different places. The ability, however, that butterflies 

 have to rest in this manner has led to the suggestion that the butter- 

 flies, which periodically migrate between Ceylon and India, avail 

 themselves of the habit whilst crossing. 



The Giant Flea: Hystrichopsylla talpae {u'ith plate). 



By the Hon. N. C. EOTHSCHILD, B.A., F.L.S., F.E.S. 



Entomologists, particularly coleopterists, from time to time come 

 across the giant flea {Hystrichopsylla talpae). This insect would 

 probably escape notice altogether were it not for its phenomenal size, 

 it is in fact the largest species hitherto recorded, being no less than 

 5-5 mm. in length. During the last few years I have received several 

 specimens of this insect from British entomologists, and as a slight 

 recompense for their kindness I have endeavoured to give an accurate 

 figure of one of the strangest British insects. 



The Siphonaptera, though possibly the most succinct and highly 

 specialised group of insects found in Great Britain, have hitherto 

 received but little attention from English entomologists. The 

 accompanying figure, drawn by my friend Dr. Jordan, will no doubt 

 interest those entomologists who have captured specimens of H. talpxie, 

 and may possibly induce others to give attention to this very interest- 

 ing family of parasitic insects. Hystrichopsylla talpae was originally 

 described and figured by Curtis", and has been figured again by 



* Brit, Ent., iii. (1826), no. 114, Fig. 



