NOTES ON THE GENUS PLATYCOTIS STAL. 



H. L. DoziER. 



The genus Platycotis is represented in the United States by 

 two distinct color varieties of one and the same species, Platy- 

 cotis vittata Fabr., and a smaller, pale yellow species, P. minax 

 Godg. which is found in California on oak. 



Van Duzee gives the distribution of P. vittata as follows: 

 N. J., Pa., Md., D. C, N. C, Ga., Fla., Texas, Ariz., Calif., 

 Vane. Isd (Mexico). The writer found last instar nymphs on 

 oak at Columbia, S. C, April 23, 1918. 



P. vittata and its color variety quadrivittata have long been 

 regarded as two distinct species on account of coloration. The 

 fact that each of these also is found in two forms, with and 

 without a porrect horn, in both sexes has only added to the 

 synonomy of the species. 



This confusion seems to be cleared up by the following 

 observations, which were made at Gainesville, Fla., while 

 attempting to work out the life history. A colony of sixteen 

 males and fourteen females, all typical quadrivittata adults, was 

 confined about the first of April, 1918, on an oak limb, enclosed 

 in a new bobbinet netting for observation. This colony was 

 confined at the edge of "hammock" forest under natural con- 

 ditions, being on the same limb from which the colony was 

 taken e?t nature. 



Observations were made every few days but no eggs were 

 deposited. On April 17, a little over two weeks, all were living 

 but had changed in markings from quadrivittata to almost 

 typical vittata. They had lost all of the lines, except a bare trace 

 of the one on side of pronotal horn near its end, and had assumed 

 the mottled appearance of vittata. On this date observations 

 were discontinued due to the writer leaving Florida. Whether 

 the change in markings was physiological, due to being confined 

 or whether it is a question of senility or what is unknown. 



This seems to prove conclusively that these two color varie- 

 ties are the same species. This is the position taken by Van 

 Duzee in his "Check List of Hemiptera." 



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