PLATE 28 



EXPLANATION OF FIGURES 



Fig. 37 Photomicrogra])h of a transverse section of a twenty-three-day rain- 

 bow trout embryo, taken tlirovigh the caudal end of the left subocular lymph sac 

 {!)] showing that the superficial facial {21) and lateral pharyngeal lymphatic 

 communicate with the subocular lymph sac at this stage of development; com- 

 pare figure 37 with figure 16. P. E. C. 968, slide 1, section 112. 



Fig. 38 Photomicrograph of a transverse section of a twenty-three-day rain- 

 bow trout embryo, taken through the left subocular lymph sac (1) eleven sec- 

 tions anterior to the point (fig. 37) where the superficial facial lymphatic {21) 

 communicates with the lateral pharyngeal lymphatic and the subocular sac. P. 

 E. C. 968, slide 1, section 101. 



REFERENCES 



1, Subocular lymph sac 21, Superficial facial lymphatic 



130 



