1002 ENTOMOLOGICAL SOCIETY. 79 



NOTES ON SEMIOPHORA YOUNGII, SMITH. 

 By Arthur Gibson, Ottawa. 



In the report of the Dominion Entomologist for 1901, on page 251, mention is made of a 

 new enemy to taraarac, or the American Larch {Larix Americana, Mx. ) and the Black Spruce, 

 (Picem. nigra, Poir.), viz., Semiophora Younqii, Smith. This insect occurred in sufficient 

 numbers in a large peat swamp near Ottawa to cause considerable destruction. A notice of 

 this is also made in an account of " A Day at the Mer Bleue, Eastman's Springs, Ont." by 

 the writer. (Rep. Ent. Soc. Ont. 1901.) During the past season further observations were 

 made on the life-history of the species, but our knowledge of the habits of the insect is still 

 far from complete. 



On the 21st May, 1902, a trip was made to the Mer Bleue, by Mr. Young and the writer, 

 but only a few larva3, from half to three-quarters grown, could be found, and these were very 

 local. At this point, owing to recent fires, the only trees on the swamp are small tamaracs 

 and spruces from two to four feet high, and what larvpe we did find were all hiding in the wet 

 moss at the base of the tamarac trees, a few inches below the surface. No specimens could be 

 found near the spruce trees. A great many trees in other parts of the swamp were examined, 

 but in only the one spot could specimens be found. In every case it was necessary to search 

 in the moss at the base of the tree to find the larvse as no noticeable injury to the foliage could 

 be detected. The mature caterpillar is a handsome creature "about an inch and a half in length 

 when full grown, of a rich velvety brown, with a ruddy or greenish tinge in different specimens, 

 the dorsal area showing the richest colours, and bounded on each side by the white clear and 

 threadlike lateral stripes ; the dorsal stripe of the same intensity as the lateral stripes ; the 

 spiracles black and lying on the upper edge of a broad white substigmatal band, the lower 

 surface much paler than the dorsal, the whole body finely mottled with small purplish brown 

 spots. The centre of each segment on the dorsum is darker and more velvety than the inter- 

 segmental folds. The head is reddish brown finely mottled with lighter spots. " (Fletcher.) 



On the 18th September another visit was made to the locality in the hope of collecting 

 some of the imagoes. At this time the moths of the Cranberry Looper, Caterva caUnaria, 

 Cram., were in great evidence — hundreds and hundreds of specimens in perfect condition. At 

 almost every step four or five of these moths would arise from their resting places, and flutter 

 away. Unfortunately, however, we were too late to secure good examples of the moths of 

 Semiophora Youngii, Smith, but in all five specimens were taken, three by Mr. Young and two 

 by the writer. These five specimens were in poor condition and were all collected at rest on 

 small taraarac trees. Mr. Young put one of his specimens, a female, into a chip box, and 

 secured some eggs, half of which he gave to the Division of Entomology. These were laid on 

 the 19th Sept. and the young larv;e hatched out of doors on the 28th and 29th Sept. The 

 following brief description was taken of Stage I — Head, brown. Body cylindrical, semi- 

 translucent, pale greenish after feeding. Thoracic shield concolorous with head. Tubercles 

 black and shiny. No markings on the body. The young larvai loop when walking. 



On the 16th Oct., in company with Dr. Fletcher and Mr. W. S. Odell, an enthusiastic 

 microscopist, another trip was made to the Mer Bleue, and on this occasion two pupae, of what 

 we take to be Semiophora Youngii, Smith, were found by the writer, in the moss at the base of 

 a small tree. One of these was dead, but the other contained a living, rather large hymenop- 

 terous parasite, almost fully formed, which could be distinctly seen moving inside. This pupa 

 has been kept in a warm office ever since, but the parasite has not as yet emerged (1st Dec.) 

 although still active inside the pupa.* 



* Since the above was written the parasite has emerged, and Mr. Harrington tells me that it is a species of Anomalon , 

 ot previously taken here and unknown to him. 



