March, 1904.] Banks : New Species of Injurious Mites. 53 Cyphoderris monstrosa piperi, new variety. Distinguished from the typical monstrosa by the average greater size, rougher and more opaque surface of the pronotum and by the color of the pronotum. In structure like vionstrosa but different in general appearance. Pronotum more opaque and mesially more profoundly incised dorsolaterally, in the male the posterior lobe rising more rapidly posteriorly and the surface much more coarsely ridged longitudi-nally than in the typical monstrosa and the deep black of the anterior lobe is less glistening and is continued across the lateral lobes to the posterior border and thence along the hind border across the top, leaving only the center of the pronotum and the lower margin of the lateral lobes without infuscation. Length, male, 27 mm., female, 31 mm.; pronotum, male, 8.5 mm., female, 7 mm.; posterior femora, male, 12 mm., female, II mm.; wings beyond pronotum, male, 8.5 mm., female, I mm. Type. — No. 7723, U. S. National Museum. The collector, in whose honor this interesting variety is named, furnishes the following note on the habitat of the insect : "These specimens were collected in Paradise Valley on the south side of Mt. Rainier, Washington, at the point called ' camp of the clouds,' altitude about 6,000 feet. They were collected during the daytime hidden under debris in a grove of alpine fir. No memoran-dum was made concerning their notes." Class III, ARACHNIDA, Order I, ACARINA, FOUR NEW SPECIES OF INJURIOUS MITES. By Nathan Banks, Washington, D. C. (Plate II.) The following four new species of mites are all of considerable economic importance. They have been received by the U. S. Depart-ment of Agriculture, Division of Entomology during the past year. The manuscript names of some of them have already appeared in print, therefore it is useful to have the technical descriptions issued at an early date.