14 THE BIOLOGICAL REVIEW. 



dinal lines, slightly elevated ridges and ragged transverse eleva- 

 tions, resembling leaf scaurs. 



The interior consists of uniform, soft, white pith, through 

 which the larvae tunnel. 



On April 20, 1892, I made a collection of forty- seven galls and 

 placed them in a glass jar ; they were pitted with numerous 

 small holes, and many of the occupants had evidently emerged. 



On April 24, 1892, several cecidomyid larvae had emerged, and 

 were resting on the bottom of the jar ; they were of a pale orange 

 color, 3 mm. long, 0.4 mm. diameter. 



The average size of ten of the largest and most cylindrical of 

 the galls was 35 mm. by 12 mm.; diameter of stems under 

 galls, 4 mm. ; of ten of the upper and more spherical, 5 mm. 

 by 4 mm. ; diameter of branchlets under galls, 2 mm. 



From May 30, 1892, to June 8, 1892, twenty-seven specimens 

 of diplosis emerged. 



From May 30, 1892, to June 23, 1892, numerous parasites of 

 two species emerged. 



On July 26, 1892, full-grown galls were found in growing 

 plants, uniform in color with the stems of the plants ; a few 

 plants with galls were transplanted to the garden and carefully 

 watched. Diplosis larvae began to emerge October 15, 1892. 



On November 13, 1892, a lot of seventy-three galls was col- 

 lected from several localities, and all from diminutive plants. 



The average size of ten of the largest, from the stems, was 

 35 mm. by 8 mm. ; diameter of stems under galls, 4 mm. 

 Average size of ten of the more spherical, from the branches, 

 3 mm. by 2 mm. ; diameter of twigs under galls, 1 mm. 

 These galls were pitted with minute holes. 



From May 11, 1893, to June 19, 1893, numerous parasites of 

 two species emerged — an Ormyrus and aPteromalus. 



From June 7, 1893, to J une I 5' 1893, several pairs of pro- 

 ducers emerged. 



The producer of this gall, for which I propose the name Diplo- 

 sis eregeroni, bears a close resemblance to several of the cecido- 

 myid gall-producers on herbaceous plants, and a recognizable 

 description must be based on a full and careful comparison with 

 these, many of which are undescribed. 



