42 JOURNAL OF ECONOMIC ENTOMOLOGY [Vol. 9 



ordinary type and well open to air. The plants and soil in these was 

 kept well moistened during the whole period and the plants made fine 

 growth and excellent color. The cages of Series B were similar to the 

 first but with glass sides and top. In each Were suspended two light 

 porous cylinders filled with lime chloride. These cylinders were fre- 

 quently removed and dried. Moisture was supplied to the plants in 

 these cages by a sort of subsoil irrigation system devised as follows: 

 The upper two inches was of ordinary compact soil, below this was two 

 inches of sand and below this a mixture of soil and sand. From the 

 sand layer, or aquifer, a one-half -inch tube extended up one side of the 

 cage through which water could be supplied to the roots. Every effort 

 was made to simulate the conditions of a drought. The growth of the 

 plants in these cages, while fairly good, was not so vigorous or so deep in 

 coloration as in Series A. Examination of the stems of plants thus 

 grown led to the conclusion that the borers thrive best under condi- 

 tions of drought. This was fully borne out by field. records for the 

 past two years. The fall brood of 1915, after a season of exceptional 

 rainfall, was notably smaller than that of 1914, after a season of ex- 

 ceptional drought. 



Cassida pallidula Boh. 

 Among the other interesting insects noted commonly on Solarium 

 carolinense L. was this beautiful pale green, deeply pitted tortoise 

 beetle. The larva is of the type common in the group, with its curious 

 anal forks bearing an umbrella of excrement above its back. Larvae 

 were abundant on wild plants of the horse nettle and on June 30 a 

 number were placed on both tomato and potato in separate cages. 

 They began feeding at once and on July 9 pupation occurred, the 

 adults emerging on the 14th. On July 15 copulation was observed 

 on tomato and on the 17th eggs were found on the plants in this cage, 

 while on the 19th eggs were also found on potato. The eggs are sub- 

 cylindric, slightly flattened ventrally and with rounded ends and are 

 enclosed in transparent sheaths. They are green in color at first, 

 soon changing to brown. The eggs hatched in from 9 to 13 days and 

 the larval period of the second brood was about one month. The 

 pupation period was from 6 to 10 days. 



Gargarphia solani Heid. 

 Another abundant and interesting insect on the horse nettle was this 

 Tingitid bug, which, unknown to us at the time, had been recently 

 discussed by David E. Fink in U. S. D. A. Bui. 239, where it is called 

 the "Egg Plant Lace Bug." Since our data has been largely antic- 

 ipated by this paper we will touch but briefly upon this insect. Spec- 

 imens were transferred to both tomato and potato in separate cages 



