Interbreeding between strains of Tetranychits telarius (Linnaeus), T. urticae Koch, and T. yutsti McGregor was attempted. The only crosses producing fertile hybrids were those between British T. urticae and Maryland T. telarius. The hybrids, their daughters, and offspring of backcrosses were used to study fertility and inheritance of body color; integumentary lobe type, and egg color. The F1 hybrid females were orange-red and later pink, and usually possessed dorsal integumentary lobes similar to those of T. urticae. There was great variation in the F2 females and the offspring of backcrosses. The results indicated that red color is at least partially dominant over green, and that the tall, narrow, pointed dorsal integumentary lobes of T. telarius are recessive to the more rounded ones of T . urticae. Inheritance of egg color is frequently correlated with body color, with reddish females laying pigmented eggs, greenish on es nonpigmented eggs. It is suggested that further cytogenetic study and analysis is necessary to clarify ail the findings presented. The few fertile hybrids produced suggest that hybridization occurring in nature between T. urticae and T. telarius can complicate taxonomie studies of the complex.