119 



Mr. S. Stevens coimnunicatecl the following extract from a letter from Robert 

 Clark, Esq., and exhibited a specimen of the fly alluded to therein : — 



" These insects are pretty numerous in the windward division of the Gold Coast, 

 in March, April, May, November and December, esjiecially in the three former months, 

 before the first rains set in, when the weather is generally close and oppressively hot. 

 As soon as they are observed, either in or about the houses of the Europeans or natives, 

 everything is done to get rid of them, for when they alight on the person they inflict a 

 painfully stinging wound, rapidly followed by a wheal, which becomes the seat of an 

 annoying itchiness. The proboscis, as you may have noticed, is strong and keen, and 

 they readily push it through thick clothing and thin leather. Horses and other beasts 

 of burden sufi"er severely from their attacks, and there are good grounds for believing 

 that this is the cause why no animal of that description will live upon the windward 

 part of the Gold Coast; indeed, my friend Mr. R, D. Ross was so persuaded of this 

 being the case that he made a strong representation to the head of the Commissariat 

 Department to that effect, suggesting, at the same time, that hammock instead of horse 

 allowance should be granted to the officers of the G. C. A. Corps stationed in the wind- 

 ward districts. 



" In 1858 I procured from the late Mr. Consul Campbell, of Lagos, four horses 

 for the use of some of the officers stationed at Cape Coast Castle. They arrived in 

 fair condition, were well stabled, carefully groomed and fed, nevertheless in six or 

 eight weeks from the date of their landing they were all dead. This did not seem to 

 me to arise from the grass, as it was in every respect quite equal to that on which 

 horses feed and thrive admirably on the leeward division of the Gold Coast, at Sierra 

 Leone and the Gambia. The precaution of partly drying it before it was given to the 

 animals was uot neglected, and their food was varied with ground nut-straw, which is 

 considered capita! fodder for horses both at Sierra Leone and the Gambia. The late 

 Mr. Brodie Cruikshank even imported hay and oats from England, conceiving (I am 

 of opinion incorrectly) that the mortality of beasts of burden depended upon some 

 poisonous herb being mixed up wilh the grass on the part of the Gold Coast I refer 

 to, but as might be anticipated the experiment in question proved a complete fiiilure. 



"With regard to these insects I think I told you that a Mr. Glydden, purser of 

 H.M. store ship ' Buffalo,' to whom I showed them on the Coast, insisted that they 

 are identical wilh the tzetze described by Dr. Livingstone, alleging that he had met 

 with them in some of the regions of Southern Africa which he had visited." 



Mr. Westwood remarked that the insect exhibited was closely allied to the common 

 Tabanus bovinus of Europe, and certainly not the " tzetze " met with by Dr. Living- 

 stone and others, as was asserted in the latter part of the letter just read. 



Dr. Wallace communicated the following: — 



Remarks on the Occurrence of Rarer British Sphingidce. 

 " The fact that in many female Sphingidae captured in Great Britain and Ireland, 

 in the autumn months, no ova have been found, induces the question as to whether 

 some species may or may not be continuously indigenous. Many think that the absence 

 of ova in the female is merely a question of time, as in the case of A. Atropos, the 

 females of which, notoriously devoid of eggs in the forced autumn specimens, are found 

 in June depositing ova, whence the brood is perpetuated. Others maintain that it is 



