of the Fishery Board for Scotland. 



179 



Fig. 162. Gut, I. Zoea, showing convoluted condition of the gut in the 

 rudimentary thoracic region ; g', straight anterior portion of 

 gut ; (/", portion of gut dorsal to the developing third 

 maxillipede and the pereiopods. 

 Fig. 163. Cast integument, I. Zoea, ventral view ; o. cornea ; r. rostrum, x 48 

 Fig. 164. Sternum of thorax, first young stage, t. tubercle, . . x 4S 



Fig. 165. Third swimmeret of Carcinus mamas (0^^ measuring 5| mm. 



across the broadest part of the carapace, . . . x 120 



Plate XIII. 



Fig. 166. Carapace, first young stage, . . . . . x 57 



Fig. 167. First young stage, . . . . . . x 19 



Fig. 168. Carapace of adult Cam'jiMS JTicems (^(^^ natural size. 



Fig. 169. Ventral surface of first young stage. The hairs, etc., on the 



external surface of the abdomen are not shown, . . x 57 



Fig. 170. Third young stage (drawn from a moulted integument), . x 19 

 Fig. 171. Carapace of a fourth young stage, . . . x 19 



Fig. 172. Half of carapace of a young Carcinus mcenas measuring 



5"5 mm. across, . . . . . . x 10 



Fig. 173. Second young stage, . . . . . . x 19 



Fig. 174. First and second joints (protopodite), second maxillipede, 

 IV. Zoea. 



