96 PROCEEDINGS OF THE NATIONAL MUSEUM VOL. IM 



E. pipistrelli Brennan, Journ. Parasitol., vol. 33, pp. 249-251, figs, 3A-D, 1947. 



Locality: Mud Cave, Stone County, Mo. 



Type host: Pipistrellus subflavua subflavue (F. Cuvier). 



Type slide: Rocky Mountain Laboratory. 



Synonym: E. miricoxa Brennan, Journ. Parasitol., vol. 34, pp. 465, 

 468-469, 477, figs. 3a-e, 10, 1948. 

 E. samboni (Radford), Parasitology, vol. 34, pp. 76-77, fig. 99, 1942. 



Locality: Ross's Hole, Mont. 



Type host: Pika [Ochotona]. 

 E. aciuricola (Ewing), Amer. Journ. Trop. Med., vol. 5, pp. 261, 262, 1925. 



Locality: Florence, Mont. 



Type host; Sciums [= Tamiasciurus'] htidsoniais richardsoni Bachman. 



Type slide: U. S. National Museum No, 892. 



Synonym: E. americana Ewing, Joura. Washington Acad. Sci., vol, 28, 

 p. 293, 1938, 

 E. setosa (Ev/ing), Proc. Biol. Soc. Washington, vol. 50, pp. 170, 171, 1937. 



Locality: Okefenokee Swamp, Ga. 



Type host: Peromyscus gossypinus gossypimis (LeConte). 



Type slide: U. S. National Museum No, 1256, 



Culture and life history : Knowledge of the life history of 

 trombiculid mites has been acquired mostly by rearing them in 

 the laboratory. The Japanese were the first active workers on 

 chigger culture. During the early years of this century, they 

 were trying to determine the development of the vector of 

 tsutsugamushi disease. However, the first report of rearing 

 chiggers was that of Kneissl (1916), who obtained nymphs in a 

 culture jar with soil from engorged larvae of Trombicula 

 autumnalis. The next year, 1917, Miyajima and Okumura reared 

 T. akamushi through all its life cycle. They described and figured 

 the deutovum, larva, nymphochrysalis, nymph, imagochrysalis, 

 and adult, but they failed to find the egg. They used soil in jars 

 for their cultures, apparently, and gave the nymphs and adults 

 pieces of potato and mellon as food. Hatori (1919) described 

 rearing engorged chiggers through the adult stage in vitro with 

 soil, but attempts to culture them on vegetable matter in vitro 

 failed. Ewing (1925a) reported the first effort at rearing chiggers 

 in the United States. He obtained larvae from a wild-caught 

 female Trombicula alfreddugesi (Oudemans, 1910) which he kept 

 on a disc of cork placed on sand in a vial. Springtail fecal pellets 

 and a dead springtail were offered as food. Miller (1925a, 1925b) 

 reported obtaining adults of T. alfreddugesi from engorged lai-vae 

 shed from infested snakes kept in suitable "aquaria" with soil. 

 However, Ewing (1944b) stated that Miller reared nymphs, not 

 adults. Ewing (1926a) reared 28 nymphs and two adults of 



