78 THE YOUNG OF THE CRAYFISHES ASTACUS AND CAMBARUS 



Plate IV. 



Figure 2T. Outer face of left mandible of second stage. 2. A. 



28. Inner face of left mandible of second stage. 2. A. 



29. Outer face of left first maxilla of second stage. 2. A. 



30. Outer face of second maxilla of second stage. 2. A. 



31. Outer face of first maxillipcd of seccmd stage. 2. A. 



32'. Outer face of left second nuixilliped of second stage. 2. A. 



33. Outer face of left lliird maxillipcd of second stage. 2. A. 



34. Posterior face (d' lid't clicla of second stage. 2. A. 



Platio v. 



Figure 3.5. Posterior face of kd't second walking leg, second stage. 2. A. 



36. Posterior face of left third walking leg, second stage. 2. A. 



37. Posterior face of left fourth walking leg, second stage. 2. A. 



38. Posterior face of left fifth walking leg and plcuro branch. 2. A. 

 30. Posterior face of a left pleopod of second stage. 2. A. 



Pi.ATK vr. 



Figure 40. Dorsal aspect of living larva in ihclliird stage in normal atliliidc whii-li makes 

 llii' lelson fore-shortened. 2!I0 iimi., aa. 



41. Side view of living tliird-stagc 1ai-\a kept (juiet by alcohol. 290 mm., aa. 



42. Dorsal aspect of the left newly expanded pleopod of the sixth segmenl of ihe 



third-stage larva. 2. A. 



43. Dorsal aspect of the telson of thii'd-stage larva. 2. A. 



Cambauus affinis. 



Plate VII. 



Figure 44. Posterior face of fourth left pleopod id' adult fcmalo. 200 mm., aa. 



4.5. lOggs attached to ploo|iod of adult rcnude aliout twenty hours after being laid. 



290 mm., aa. 

 4(i. N'ciilr.i! aspi't-t of posli'ri<ir |)arl of alHhinii'n of lirst larva, sltowing attachm(']it 



of telson thread, the concealed sixlli and fi-ce liftli anil fourth plropods. From 



a recently luitched larva. 2. A. 



47. Dorsal aspect of telson and sixth abdominal somite of first larva twenty hours 



after liatching. 2. A. 



48. \"entral aspect of terminal middli' part of telsiui of first larva dissected out of 



egg-shell, showing attachment of telson tliread to certain spines. 2. D. 



49. Dorsal as))ect of first larva as seen in Worcester's liquid. 290 mm., aa. 



50. Pight side of first larva, seen in Worcester's liipiid. 290 mm., aa. 



.51. Front view of eyes and rostrum of first larva, seen in Worcester's liquid. 2. aa. 



52. Pleopod covered by larva' in the first stage and 48 hours old; alive; some few re- 

 moved. Camera lucida on dissecting stand, Stcinheil Aplanatic, Xo. 9. 



5;!. Dorsal asjiect of left antennule of first stage. 2. A. 



54. Lower face of left antenna of first stage. 2. A. 



55. Outer face of left mandilile of first stage. 2. A. 

 5(). Outer face of left first maxilla of first stage. 3. A. 



57. Outer face of left second maxilla of first stage. 2. A. 



' In Fiiis. :ii> til :',7 tlie anterior artlnnlnanrli is dotleil for ilistinctne 



