12 



MR. H. G. CANNON ON THE ZO.EA 



(text-figs. 3 & 4) and the second antenna does not bear a lateral 

 spinous process (text-fig. 4). The 1st abdominal segment bears 

 at each. side a short forwardly directed spine, the other segments 

 being unarmed (text-fig. 2). The endopodite of the 1st maxilliped 

 is five-jointed, the second joint being the longest (text-fig. 5). 

 The exopodites of the 1st and 2nd maxillipeds end in a group of 

 four short-pointed setae arranged side by side (text-fig. 5). There 

 is a large branched pigment-spot on the ventral side of the 

 abdomen between each pair of segments and a small circular 

 patch of pigment on the distal end of the protopodite of the 

 1st maxilliped (text-figs. 1 & 2). 



Comparison with the description given by Moreira [1912] for 



Text-fisfure 1. 



Text-figure 2. 



Lateral aspect of 1st zosea of Cardi- 

 soma armatum. X 88. 



Dorsal aspect of 1st zoaaa of Cardi- 

 soma armatum. X 88. 



the zosea of C. guanhumi shows only one marked difference. In 

 G. guanhumi it is stated that the cephalothorax is provided solely 

 with a dorsal spine, the anterior and lateral spines being absent. 

 Between two such nearly related forms as C. guanhumi and 

 C. a7^matum it would not be expected that such a diflerence would 

 occur. However, the figures illustrating Moreira's paper suggest 

 that a re-examination of the South-American form might be 

 desirable. 



An account of the 1st zosea of Gelasimtos by Hyman [1920] 

 indicates a close similarity with the zoaea of C. armatum. In this 

 form, however, there are no lateral spines on the cephalothorax, 

 although the anterior spine is present. 



