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day in huts thatched with palm leaf, but are difficult to get from the houses inhabited by Europeans and better class Chinese, except perhaps in dark corners and recesses. They have been captured in cow houses and pigsties in the New Territories. They are of the greatest importance as malaria carriers and also harbour filarial worms which are most likely derived from human
sources.
Larvae of A. jeyporiensis were met with in numbers only during the last quarter of the year. They have been found in hill streams like the preceding, but the great majority were obtained from grassy swamps. They have also been found in grassy seepages and in wet cultivation. Most of the adults were obtained by catching during the last quarter of the year.
These mosquitoes have been found infected with malaria; filaria worms have also been found in them but not in an advanced stage of development.
Very few larvae of A. karwari, A. tesselatus, A. maculipalpis and A. aitkenii were encountered during the year. Unless careful examination is made there is considerable danger of confusing the larvae of A. maculatus, A. karwari, and A. maculipalpis. Some A. minimus larvae have got poorly developed tergal plates but attention to other details will prevent a mistake. Some ten- tative feeding experiments on the human subject were made with A, hyrcanus, A. maculatus, A. minimus, and A. jeyporiensis, obtained from larvae hatched out in the Laboratory. The insects were kept in lamp glasses covered at both ends with mosquito netting, these were stood on damp lint. After hatching, the mosquitoes were allowed access to raisins for a day, later, by withholding the raisins, the majority could be induced to bite and take blood, in the case of A. maculatus, the raisins had to be withheld for two days but not so in the case of the others; A. hyreanus fed most readily.
Culicines.
Larvae and adults of the following were obtained during the year. Aedes albopictus, togoi, japonicus, macfarlanei. C. quin- quefasciatus (fatigans), C. vishnui, C. bitaeniorhynchus, C. mimeticus, C. (Culicioyinyia) pallidothorax, C. virgatipes, Armi- geres obturbans, Megarhinus splendens, Mansonia uniformis, Uranotaenia macfarlanei, a species of Uranotaenia and species of Lutzia. The following hitherto not recorded for Hong Kong have been met with and identified as Aedes niveus, Armigeres magnus, a species of Taeniorhychus, a species of Ficalbia (probably Fical- bia luzonensis) a species of Armigeres, probably Armigeres malayi. Specimens of these have been sent to Mr. Edwards of the British Museum for his opinion. Two species of Cerato- pogoninae were identified by him as Culicoides anophelis (Edw.). and as Lasiohelia (probably L. stimulans de Meig.). The former has been caught on several occasions attached to A. minimus, the latter is the little dark fly which bites viciously in the hot
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weather. What appears to be a species of Culicoides has also been found on C. fatigans. Larvae found in a pitcher plant by Dr. Herklots were identified as those of Armigeres magnus, and
a species of Culex. By hatching out single larvae and mounting the larval and pupal skins thrown off, endeavours were made to obtain as many specimens as possible of mosquitoes and the corresponding skins. It would seem by this method that other spotted wing species of Culex akin to Culex mimeticus are to be found in this part of the world. Mounts of the Culicine larvae in pure Carbolic ringed with Canada Balsam, have turned out most satisfactory.
Specimens of larvae have been received from Dr. Hu, Nan- king, and of mosquitoes from Dr. Li, Hangehow. Specimen of mosquitoes and their larvae have been sent to Dr. F. W. Edwards. British Museum, Dr. W. V. King, Mosquito Investi- gations, Bureau of Science. Manila, to Major Covell and Captain Barraud (Malaria Survey of India, Kasauli), to Dr. Li, Bureau of Entomology, Hangchow, and Dr. Hu, Nanking.
(b) MOSQUITO-BORNE DISEASES.
Malaria.
From he results of the dissections of Anophelines done dur ing 1982, it is seen that A. minimus is an important carrier in the Colony. During the last quarter of the year A. jeyporiensis was also found infected. I is hoped during the coming year to get a larger number of dissections done in the early months than were done in 1932 in order to ascertain with greater certainty how matters stand as regards the infection rate during this period. It would appear from the 1932 dissections that malaria is more prevalen: in the second half of the year, no infected glands being found until the middle of June when over five hundred A. minimus had been dissected from a malarious area. If this is borne out by further research the incidence in the first half must be largely due to relapses and infections from the previous year. Records obtained from the R.A.M.C. authorities indicated as formerly, a much higher incidence for the second half of the year, forty-one fresh cases out of a total of forty-five fresh cases amongst British troops; eighteen out of twenty-four amongst Indian roops. The figures for Lai Chi Kok Gaol (male) which is close to a hill stream where A. minimus has been found, were eighty-seven cases of malaria for the year, sixty-six of which occurred from July onwards. The 1930 and 1931 figures show the same seasonal incidence. Amongst the Government servants (excluding coolies) our of one hundred and fifty-c cases diagnosed as malaria, one hundred and thirteen occurred during the latter half of the year as was similarly found in 1930 and 1931.
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Statistics for 1932 obtained from M.O.H. show that 455 deaths were ascribed to malaria in the Colony and New Territor- ics, these being 2.28 per cent of the to al deaths. The death
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