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Indiana Universitij Studies 



Museum of Comparative Zoology, and the Beutenmuller collection (?). 

 From the neighborhood of Jacksonville (?), Florida; Ashmead collector. 



At this time I can add little to our knowledge of this 

 species because I do not have insects enough to determine how 

 many varieties it may have, and the range and hosts of each. 

 The above descriptions, made from types, will separate this 

 species from others of the genus, and give further details 

 probably characteristic of only the typical variety. I have 

 galls from a number of localities in Florida and Georgia, rep- 

 resenting certainly more than one variety. Moreover some 

 of the galls are from Querciis virginiana, some from Q. laiiri- 

 folki, and some from Q. stellata. Probably each host has a 

 distinct form for each faunal area. The Q. stellata galls from 

 Georgia may represent a variety of Plagiotrichiis elongatiis, 

 altho the galls are more like batatoides galls. 



Dozier states that galls collected early in December gave 

 adults late in January; Weld bred adults on April 12, 1914. 

 All of my galls were collected early in November, and I failed 

 to secure adults probably because the larvae were still too 

 young when the galls were dried. These galls are pecked into 

 by birds and gnawed by mice, as Ashmead also recorded with 

 the original description. Older galls persist on the trees until 

 many of the live oaks are thickly covered with them. They 

 are the favorite abode of ants which tunnel the soft tissue, 

 further its early decomposition, and establish their colonies 

 inside. Many of the old galls are almost hollow, covered by 

 mostly complete bark, but internally a mass of thinly sepa- 

 rated tunnels and decomposing chewings. 



The insect shows very distinct relationships to the other 

 white oak species of the genus, rather than to the black oak 

 species, but in many respects it is the most unique of the 

 white oak species. The discovery of other varieties may link 

 it more directly with some other species. Plagiotrichiis 

 elongatiis riifopleurx, occurring in Texas on Querciis brevi- 

 loba, is in some respects similar to batatoides, but more closely 

 related to the other varieties of elongatus. 



Plagiotrichus chrysolepidicola (Ashmead) 



FEMALE. — Shows the following characters in addition to those 

 common to all species of the genus: Color largely rufous, sometimes 

 in part shaded to black; apical half of antenna darker than basal half; 

 mesonotum closely, finely puncto-rugose, sometimes in part puncto- 



