6 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 121 



show some signs of pigmentation. They frequently occur in clusters 

 of more than 100 individuals on the fins of the shark. 



Members of this genus can easily be separated from other genera 

 on the basis of the arrangement of the dorsal thoracic plates and the 

 nature of the caudal rami. 



Key to Adult Females of Pandarus 



1. Dorsal plate of thoracic segment 2 extending only as far as ttie posterior edge 



of the plate of segment 3 BICOLOR GROUP. 2 



Dorsal plate of thoracic segment 2 extending well beyond posterior edge of 

 plate of segment 3 CRANCHII GROUP. 4 



2. Cephalon only Ys of total body length; caudal rami small, scarcely visible 



dorsally bicolor 



Cephalon about }^ of total body length; caudal rami easily visible dorsally . 3 



3. Caudal rami long, about 3 times as long as dorsal abdominal plate and extend- 



ing well beyond it; posterior edge of plate of segment 4 without conspicuous 



sinus niger 



Caudal rami only about 1^2 times as long as dorsal abdominal plate and 

 extending only slightl}^ beyond it; posterior edge of plate of segment 4 with 

 deep sinus carcharhini 



4. Caudal rami with the inner basal half expanded to broad lobe . . smithii 

 Caudal rami without such a lobe 5 



5. Caudal rami not extending more than ji length of dorsal abdominal plate. 



satyrus 



Caudal rami extending at least to tip of dorsal abdominal plate or well 



beyond it 6 



6. Dorsal plates of thoracic segments 3 and 4 fused and with broad posterior 



sinus 7 



Dorsal plates of thoracic segments 3 and 4 divided by deep sinus into 2 

 nearly separate lobes 9 



7. Dorsal abdominal plate subtriangular; eye spots separated in fully pigmented 



forms cranchii 



Dorsal abdominal plate subcircular; body may or may not be darkly pig- 

 mented 8 



8. Most of body darkly pigmented but eye spots connected by median posterior 



line sinuatus 



Body only slightly pigmented with pigment usually couhned to anterior 

 portion of cephalon and plate of fourth thoracic segment . . . fioridanus 



9. Thoracic plate of segment 2 extending to posterior tip of thoracic plate of 



segment 4 zygaenae 



Thoracic plate of segment 2 extending to middle of thoracic plate of seg- 

 ment 4 katoi 



Pandarus satyrus Dana, 1852 



Figures 1-26 

 Pandarus satyrus Dana, 1852-3, p. 1368. — Brady, 1883, p. 134. — Bassett-Smith, 

 1899, p. 467.— Wilson, 1907, p. 415; 1914, p. 71.— Yamaguti, 1936, p. 5.— 

 Bere, 1936, p. 595.— Shiino, 1957, p. 364; 1959a, p. 315; 1959b, p. 352; 

 1960b, p. 493.— Ho, 1963, p. 90. 



