L. DONCASTER 21 



PLATE 2. 



Fig. 14. Egg of '13.3. Secoud polar mitoses, side view, to show the appearance resembling 

 cilia. Combined from two successive sections. 



Fig. 15. Egg of '13.4. Showing two maturation figures in one egg. The two parts of 

 the figure are drawn from sections five sections (50;n) apart. 



Figs. 16a, 16b. Egg of "13.42, with two maturation figures in one egg. 



Fig. 16a. Combined from two successive sections, showing three polar nuclei, the two 

 inner in contact, in each maturation figure. The outer nuclei of both figures are in 

 one section, the two inner pairs in the next. 



Fig. 16h. Conjugation of the two female pronuclei with two sperm-nuclei. Combined 

 from the two sections next following the sections from which 16(( was drawn. Note 

 that the sperm-radiations are sinuou.s, bifurcate, and those of one system cross those 

 of the other. The clear space around the conjugating nuclei is due to contraction at 

 fixation. 



Fig. 17. ? of '12. '25. Oogonial equatorial plate with 5.5 chromosomes. (Only 54 

 are visible in the figure ; one has been accidentally omitted.) 



Fig. 18. Another ? of '12.25. Oogonial equatorial plate with 56 (exceptional). The 

 only doubt about the number 56 arises from the fact that the two chromosomes 

 marked x might possibly be one in division. Since the outer is itself double, this is 

 very improbable. Drawn with Zeiss 2 mm. apochrom. n. ap. 1'40, compens. oc. 12. 



PLATE 3. 



Fig. A. Female parent of brood '12.25. 



Figs. B, C. The two grossulariata females which appeared as exceptions to the normal 

 sex-hmited transmission of the gross, character, in brood '12.25. Note the close 

 resemblance of the pattern in the two specimeus, and their general resemblance 

 to their mother. The chief peculiarities are 



(a) the union of the costal and discal spots to form a definite hook-shaped or 

 ?-3haped mark across the middle of the fore-wing ; 



(h) the reduction, but not complete absence, of the spots at the tip of the fore- 

 wing on the outer side of the yellow band ; 



(c) the union of the basal line of spots on the hind wing into a continuous band, 

 from which the discoidal spot projects outwards, but is continuous with the band ; 



(d) the almost complete union of the distal row of spots on the hind wing, and 

 the absence of the most anterior marginal spot, which ia usually present at the costal 

 angle. 



These points are indicated by letters in Fig. C. 

 Fig. D. A grossulariata female of brood '12.15, closely related to '12.25. This is the 



specimen most nearly resembling the gross, females of '12.25 among the moths bred 



in 1912. 

 Fig. E. Atypical grossulariata female; showing the difference between the females of 



'12.25 and ordinary grossulariata. 



