OF WASHINGTON. 167 



stained disks resembling red blood corpuscles, about 3 microns 

 in diameter, many large fat globules, a few mononuclear cells, 

 and no micro-organisms; otherwise negative. 



As above stated, the larvae feed only at night and try to hide 

 in their " nests " during the day, but this " hiding " becomes in 

 reality the means by which they are most easily detected and 

 destroyed, for it is much easier to cut down these " nests " 

 than to spray the trees ; nevertheless, it requires constant vigi- 

 lance on the part of the grower. Where the trees stand 

 isolated, as here on the hospital grounds, the insects are more 

 easily controlled than in a grove where the trees frequently 

 touch one another and where the caterpillars can crawl from 

 tree to tree. Altogether, the Brassolis will turn out to be a 

 most formidable enemy for the cocoanut grower if it is allowed 

 to spread, and every possible attention should be given to the 

 immediate destruction of the larvae at their first apparance. 

 I will add that I have noticed Brassolis isthmia on the follow- 

 ing wild and cultivated palms of the Isthmus, besides cocoanut : 

 Martinesia caryotccfolia, Acrocomia sclerocarpa, Oreodoxa 

 regia and oleracea, and two unidentified species of Thrinax. 



A NEW COCCID OF THE GENUS ERIOCOCCUS. 



BY T. D. A'. COCKERELL. 



I have recently received, through ! Prof. R. H. Forbes, a 

 species of Eriococcus collected by Mr. D. J. Craig at Bellevue, 

 Gila Co., Ariz., on Quercus toumeyi Sargent, occurring on the 

 small twigs in company with a species of Eulecanium. Upon 

 examination it proves to be one of the species or races of the 

 E. quercus group, distinctly differing both from true quercus 

 and from toumeyi Ckll., the latter being from Arizona, on 

 Prosopis. It may be described as follows : 



Eriococcus quercus gilensis, n. subsp. 



Ovisac pure white, ordinary, about 4 mm - long. On boiling in caustic 

 potash the insect does not stain the liquid pink. Dermal spines strong, 

 about 45 A* long. Tibia always longer than tarsus. Antennae 7-jointed, 

 joint 4 always longest, longer than 3, which averages a little longer 

 than 7; 5 and 6 short and equal. 



The following measurements are in M. Femur and trochanter : Middle, 

 190; hind, 205. Tibia: Anterior, 125; middle, 145; hind, 150. Tarsus 

 (without claw): Anterior, 67; middle, 75; hind, 82. Antennal joints, 

 different examples: (2) 37^, 30, 30; (3) 42^/2, 42^/2, 37 l /2, 35 J (4) 57^2, 



