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kind of span-worin on some apple and prnne trees as well as on Eng- 

 lish walnuts in some of the orchards of the above-mentioned counties. 

 Under date of April 27, 1892, Mr. Cooper writes me that he recently 

 found this pest in three other groves of English, walnut in Santa Bar- 

 bara County, where it was very destructive to the leaves of these trees- 

 Thus it appears that already this span-worm is quite widely distributed 

 over the State, and unless active measures are adopted to suppress it 

 there is every probability that it will in time very seriously interfere 

 with the profitable growing of English walnuts upon this coast. 

 Unfortunately, the moths have not yet issued, so it is impossible at the 

 present writing to identify the species or to ascertain if it has proved 

 destructive in other States than our own. 



The eggs from which these span-worms hatch are flattened oval, as 

 if compressed between the thumb and finger; the surface is quite scab- 

 rous, and bears numerous minute transverse ridges; at each end of 

 the egg are numerous quite large, shallow punctures; the color is a 

 dark greyish drab, with a strong brassy tinge; length, about £ mm . 



These eggs are fastened to the small twigs of trees, in loose, irregu- 

 lar patches, each egg lying on one of its flattened sides; there is no 

 regularity in their arrangement upon the bark of the twig. One piece 

 of a twig an inch and a half long by a quarter of an inch in diameter 

 contains upwards of two hundred of these eggs. The young span-worm 

 issues through a nearly circular hole in the larger end of the egg, and 

 the empty eggshell is of an iridescent, pearly white color. 



The full-grown span-worm closely resembles the larva of the Eastern 

 Angerona crocataria as figured on PI. vin, Fig. 6, of Packard's " Guide 

 to the Study of Insects," but the piliferous spots are larger, giving to 

 the body a much rougher appearance, and when viewed from the side 

 there is seen to be a large prominence on the dorsum of the fourth and 

 sixth segments as well as on the fifth and eleventh. I give herewith a 

 detailed description of this span-worm, in order that it may be recog- 

 nized in the future : 



Body of nearly an equal thickness throughout its length, the head and first tho- 

 racic segment slightly wider than the rest of the hody; head as seen from front a 

 trifle wider than high, the lobes rounded and destitute of a tubercle or other proc- 

 ess; color of head dark brown, variegated with yellowish; body light pinkish 

 gray varied with darker gray or purplish, or sometimes with black and yellow, never 

 marked with distinct lines ; piliferous spots tuberculiform, black, or dark brown, and 

 back of each of the spiracles situated on the fifth and sixth segments is a large, coni- 

 cal, fleshy prominence surmounted by a piliferous spot, and on the dorsum of each of 

 the segments four, five, six, and eleven, is a pair of similar but smaller prominences; 

 in front of the pair of prominences on the dorsum of the eleventh segment is a pair 

 of spots which are of a clearer yellow or gray than the ground color, each spot 

 usually bordered each side by a short black line; spiracles orange-yellow, ringed 

 with black and usually situated on a yellow spot; venter concolorous with the upper 

 side, marked in the middle with a faint whitish stripe, and with a less distinct one 

 near each outer edge; ten legs; length, 20 mm . 



