CHIGGERS — FARRELL 167 



ever, E. rubra was confined strictly to the season during which 

 soils were colder and more moist (fig. Q,d). 



E. rubra was found attached deep in the ears or in the external 

 auditory meatus of its hosts. 



Cultures : Seven cultures were started with E. rubra nymphs. 

 These were in weighing bottles or wide-mouth pint jars. One 

 v/eighing bottle was lined with moist cellulose wadding. On this 

 the nymphs soon became immobile and all were dead in less than 

 13 days. Other weighing bottles and the jars had a base of plaster- 

 charcoal. No medium for the mites was used in one culture. In 

 other cultures soil or vermiculite in combination with other mate- 

 rials was used. Aedes eggs or soil arthropods were ofi'ered as food. 

 In no culture was there any further development. Engorged 

 larvae from hosts readily metamorphosed into nymphs in special 

 vials. But nymphs in culture apparently refused all food offered 

 and soon died. 



Life history: A very limited amount of life history in- 

 formation was obtained from the culture data. It was found that 

 nymphs can develop from engorged larvae in 15 days or less. One 

 living nymph was recovered from a culture v/hich had been estab- 

 lished with four nymphs 29 days earlier. 



Remarks: The type specimen of E. rubra is an unattached, 

 unengorged specimen collected from the debris under a small, 

 decayed removable stump (pi. 2). E. rubra has been named from 

 the color of unengorged specimens. 



11. Euschdngastia magna, new species 



Figures 4,6, 6,a,6; Plates 7, 13 



Description: Size: Engorged length, 630 to 680; width, 370 

 to 475. 



Shape : Broad oval. 



Gnathosoma : General similarity to E. rubra. Lateral setae on 

 palpal tibiae with four and eight setules on one specimen, seven 

 and ten on the second specimen (fig. 6, b) . Palpal claw similar 

 to that of E. rubra but straighter, longer, and stouter. Tarsal 

 spur longer than in E. rubra. Galeal setae with four and six 

 setules on one specimen, three and six on the second specimen 

 (fig. 6,a). 



Legs : Similar to E. rubra. 



Scutum : General outline much like that of E. rubra, about the 

 same proportionate taper between anterolaterals and postero- 

 laterals, rounded posteriorly. About one-fifth larger over-all than 

 E. rubra; largest scutum in the group. Ridges and depressions 

 less strong than in E. rubra. 



