176 Pub. Puget Sound Biol. Sta. Vol. 2, No. 44 



PLATE 26 

 a, first antennae. 

 a", second antennae. 

 a.f, attachment filament. 

 a.g, first antennary glands. 

 bu, bulla. 



d, digestive tract. 



e, tripartite eye. 



/', first pair of swimming feet. 



f", second pair of swimming feet. 



f.g, frontal gland. 



f.m, frontal margin. 



ft, foot of attachment filament. 



ft.m, muscles attached to foot of attachment filament. 



g, portion of gill. 



l.l, lower lip. m.v", second maxillae. 



mnd, mandibles. mxp, maxillipeds. 



m.t, mouth tube. /, tube of attachment filament. 



ma:', first maxillae. u.l, upper lip. 



Fig. 22. Head region of first copepodid larva in contact with a 

 portion of the gill (g) prior to attachment. - The sec- 

 ond maxillae (mx") are seen rasping the gill tissue 

 (g). X197.5. 



Fig. 23. Head region of first copepodid larva immediately after 

 attachment to gill filament. Here the larva is seen at- 

 tached at its frontal margin (f.m) to the foot (ft) of 

 the attachment tube (t). The bulla (bu) is implanted 

 within the tissue of the gill (g). X 197.5. 



Fig. 24. Enlarged drawing of the frontal margin of the larva 

 represented in Fig. 23, showing the contracted muscle 

 strands (ft.m) attached to the foot (ft) of the attach- 

 ment tube (t). X415. 



Fig. 25. Anterior head portion of a frontal section of the first 

 copepodid larva, showing the natural location of the 

 muscle fibers (ft.m) which are attached to the foot 

 (ft) of the attachment filament. X415. 



Fig. 26. Drawing which shows the claws of the second maxillae 

 (mx") immediately after they have attached themselves 

 to the foot (ft) of the attachment tube (t). The bulla 

 (bu) is enclosed in the tissue of the gill (g). XI 97.5. 



Fig. 27. Attached larva undergoing degeneration. X68.5. 



