32 



GNATS OR MOSQUITOES — CHAPTER II 



negatives showing much detail by reflected hght, in which 

 case a dark background should be substituted. 



With the wet collodion process and subsequent enlarge- 

 ment, it would, I believe, be possible to produce useful 

 records of the markings, not only of Mosquitoes, but of 

 other insects. 



For certain experiments it may be necessary to trans- 

 port living Mosquitoes to a distance, and for this purpose 

 Dr. L. Sambon contrived a method, described as below in 

 the Brit. Med. Journal, September 29, 1900, p. 949, from 

 which also are copied the subjoined figures. 



Fig. 11. — Case for Mosquitoes. 



Fig. 12. — Ventilated Box for forwarding 

 Mosquitoes. 



"When the insects had fed. Dr. L. Sambon, who had 

 gone to Rome on Experiment No. 2, placed them in small 

 cylindrical cages made of Mosquito netting stretched on a 

 wire frame (fig. 11). Four such cylinders were packed in a 

 well-ventilated box (fig. 12) and forwarded to the London 

 School of Tropical Medicine through the British Embassy 

 in Rome. The box was 9in. in depth and 8^in. on the 

 sides. The wire openings were Sin. square on each side. 

 The cages were each 8|in. in length and 3^in. in diameter. 

 By the courtesy of the Postmaster-General they came for- 

 ward by the Indian mail, so that they arrived in London 

 some forty-eight hours after leaving Rome. A good many 

 of the Mosquitoes died on the journey or soon after arrival ; 

 but a fair proportion survived and appeared to be healthy 

 and vigorous." 



With respect to instrumental outfit, a good hand lens 



