574 WHEELER P. DAVEY 



to fly. Lopriori^ found a destructive action on Vallisneria 

 spiralis, Genista and Darlingtonia (dose not given). 



Perthes'' X-rayed the ova of Ascaris megalocephala giving 

 them a dose of 24 H at a voltage corresponding to 6.5 cm. spark 

 gap. Cell-division was so much retarded that although the con- 

 trol specimens were in the 4-cell stage at the end of 36 hours, 

 the rayed specimens were still in the 1-cell and 2-cell stage. 

 Hastings'^ rayed eggs of the same species, using an unknown 

 quantity of characteristic X-rays from copper. He found a 

 retardation in growth. Runner^ X-rayed the eggs of the cigar- 

 ette beetle (Lasioderma serricorne) using a Coolidge tube, and 

 giving a dose of 150 milliampere-minutes at 65 kilovolts at a 

 distance of 7.5 inches. He found that eggs less than 3 days old 

 failed to hatch, and became shrunken in about 10 days. Eggs 

 over 3 days old hatched but the larvae never reached the pupa 

 stage. Larvae similarly rayed refused to eat, and although they 

 lived a long time after raying, they never reached the pupa 

 stage. 



Oilman and Baetjer^ found that X-rays (amount not given) 

 accelerated the development of eggs of Amblystoma for about 

 10 days, but produced monsters. They also rayed hens' eggs 

 (dose not given) and found an accelerated development for 36 

 hours with the final production of monsters. Bordier and Gah- 

 mard^o gave incubating hens' eggs daily doses of X-rays of 15 H 

 each (penetration not given) for 20 days. The eggs contained 

 no embryos. In specimens which had been allowed to develop 

 somewhat before raying, growth was arrested at the first dose. 

 These results were confirmed by GaskelP^ but he makes no 

 record of dose. 



Lengfellner^- X-rayed three pregnant guinea pigs, three days 

 before term (dose not given). Two of the mothers were at 



* Lopriori, cit. Schaudin in Pflueger's Arch., 77, p. 31, 1899. 

 « Perthes, Deut. med. Woch., 30, 1904. 



' Hastings, Arch. Middlesex Hosp., 11th Cancer Report, 1912. 



* Runner, Jour, of Agr. Research, June 12, 1916. 



9 Oilman and Baetjer, Am. Jour. Physiol., 10, p. 222, 1904. 

 1" Bordier and Galimard. Jour. d'Elect. Med., p. 491, 1905. 

 " Gaskell, Proc. Roy. Soc, B 83, February 28, 1911. 

 ^^ Lengfellner, Munch, med. Woch., p. 44, 1906. 



