REPORTS OF OBSERVATIONS AND EXPERIMENTS. 20 



and the loose, fine, soft silk spun about the cocoon is less in quantity. 

 The cocoons are spun in May, and the moths issue in the latter part ol 

 that month and during the month of June. The two sexes are so dis- 

 similar in color that they might readily be supposed to belong to two 

 distinct species. The males are of a reddish brown ground color, while 

 in the females the color is a light, ocher yellow. The moths issue at 

 almost every hour of the day and night, and the sexes are evenly dis- 

 tributed. This species is Clisiocampa calif or nica Pack. 



I found but a single cluster of eggs of this species, but these had 

 already hatched and near them was the silken tent and colony of 

 young caterpillars that had issued from these eggs. This cluster was 

 attached to a small twig of a willow tree; it measures 16 mm in length 

 and reaches only two-thirds of the distance around the twig. The eggs 

 number about 150 and are arranged in irregular oblique rows; they are 

 thinly covered with a substance somewhat resembling glue, which on 

 one half of the cluster completely conceals the eggs from view. 



As in the preceding species, the young caterpillars spin a silken web 

 or tent in which to live, but after becoming about half grown they 

 desert this and lead a wandering life; they do not appear to possess the 

 habit of congregating together when not feeding, which is such a char- 

 acteristic trait of the preceding species. Besides the food-plants men- 

 tioned above, Mr. Henry Edwards states that these caterpillars also feed 

 upon the leaves of the apple, pear, oak (Quercus agrifolia), ash (Fraxi- 

 nus oregona), buckeye (JEsculus californica), California holly (Hetero- 

 meles arbutifolia), and Madrohe (Arbutus menziesii). (See Fifth Eeport 

 U. S. Entomological Commission, p. 119). 



Three different kinds of internal parasites are known to me to attack 

 these caterpillars. On the 17th of May, 1892, a larva of a Tachina fly 

 issued from one of them and soon afterward pupated. On the 9th of 

 May a larva of an Ichneumon fly spun its cocoon within the body of a 

 one- third grown caterpillar in which it had lived, causing the body of 

 the caterpillar to swell out and burst open on the underside, the cocoon 

 as spun protruding through this opening and fastening the body of the 

 caterpillar to the surface upon which it rested; the winged parasite 

 issued ten days later, and has been identified by Dr. Riley as Limner ia 

 fugitiva Say. This parasite has not previously been reported as occur- 

 ring west of Missouri, where Dr. Riley bred it from the larvae of tour 

 different kinds of moths, including the forest tint caterpillar (CUsio- 

 campa disstria Hiibn.). (See Insect Life, vol. in. p. 157). 



The third parasite referred to issued on the 28th of .May. It belongs 

 to the family Braconidae and to the genus Rhogas. 



The above two were the only species of Clisiocampa that I found in 

 the orchards of Alameda and Santa Clara counties. Neither of these 

 occurs in southern California, so far as 1 am aware, but a third species. 

 Clisiocampa constrieta Stretch, is not rare in certain parts oi Lofi 

 Angeles County, where the caterpillars teed upon the leaves o( an ever- 



