OCCURRENCE OF A SPORT IN MELASOMA (LINA) 

 SCRIPTA AND ITS BEHAVIOR IN HEREDITY 



ISABEL McCRACKEN 



Laboratory of Entomology and Bionomics, Stanford University 



With One Plate 



During the year 1904, early in the breeding season of thechryso- 

 mehd beetle, Melasoma scripta/ about 1000 pupse, and larvae, 

 in advanced stage, were collected from willows in the neighbor- 

 hood of an artificial lake near Stanford University. 



Such of these as were not parasitized matured during the latter 

 part of April and early May. The adults represented the dichro- 

 matic extremes of the species, the elytra being either spotted- 

 brown (referred to in this, as in previous papers, as "S"), or black 

 (referred to as "B"), the thorax in each case having a central 

 black area widely emarginated with brick red. In the center of 

 each red area and nearly adjacent to the central black region 

 (sometimes approximating it) is a small black spot representing 

 a single punctation. (Figs, i and 2.) 



During the course of breeding through four generations from 

 this collected material there occurred a number (four or five) 

 wholly black individuals (Fig. 3), thorax as well as wing cov- 

 ers being totally black (referred to in this paper as "AB"). Since 

 during the casual outdoor observations made throughout that 



^A description of this beetle is given in the Journal of Experimental Zoology, 1905, vol. ii, pp. 117, 

 136, and vol.iii, pp. 320-336, where it is called Lina lapponica. It seems that this identification made 

 for me is not correct. The beetle is evidently the one figured by Riley under the name Plagiodera scripta 

 (Fabr ) Ann. Rept. Agric. for 1884, pp. 336-340, pi. viii. Figs, i and 2; by Lintner, under the name Lina 

 scripta (Fabr.), Rept. N. Y. State Entomologist for 1895, pp. 181-189; and by Felt as Melasoma scripta 

 (Fabr.) in N. Y. State Museum, Memoir 8, vol. i, pp. 317-322, PI. 16, Figs. 16-20. 



The Journal of Experlmentai Zoology, vol. iv, no. 2. 



