206 



nine gills are shown. On the right side the 

 epimeral wall has been removed in order to 

 show the course of the branchio-cardiac veins, 

 and also to show the connection between the 

 latter and the pericardium. x 1. 



Fig. 55. A dissection of the epimeral region of the 

 thorax from the right side, in order to show 

 the positions of the branchial sinnses, the 

 infra-branchial sinus, the afferent branchial 

 sinuses, and also the sinuses coming from the 

 thoracic legs. x 1. 



Fig. 56. Diagrammatic section through the thorax in 

 the region of the heart, to show the blood 

 system and the general arrangement of the 

 organs. The tendons of the first walking legs 

 are shown. x 1. 



Plate X. 



Fig. 57. Dissection of the left side to show the exten- 

 sions of the bladder. The dorsal region of the 

 carapace has been removed. The fore-gut has 

 been cut through at the oesophagus and 

 removed. The gonads and the digestive gland 

 have also been taken away. The antennary 

 gland is represented by a dotted circle. x 1. 



Fig. 58: Semi-diagrammatic sagittal (vertical longi- 

 tudinal) section of the antennary gland. The 

 anterior part of the gland is to the right, 

 x 60. 



Fig. 59. Detailed drawing of part of previous figure, 

 showing the epithelial cells of the bladder, end 

 sac and the renal tubule, x 90. 



Fig. TiO. Section through the mass of cutaneous glands 

 opening on to the epistoma. x 210. 



Fig. 61. Section showing the epithelial cells of the mid- 

 gut, with characteristic striated border, x 550. 



Fig. 62. Longitudinal section through part of the wall 

 of the hind-gut, about the middle of the 

 abdomen, showing cutaneous glands, x 165. 



