49. DACTYLOPTERUS. 221 



middle series. If an artificial opening be made in it, and a coloured 

 fluid be injected, the course of the rauciferous channel, with its 

 branches, becomes very clear, the fluid spreading for a considerable 

 distance by capillary attraction. 



The lower side of the tail has two additional series of plates, sepa- 

 rated by the anal fin ; each plate has a longitudinal ridge. 



None of the dorsal spines are elongate ; the caudal fin is smaU, 

 slightly emarginate ; the pectoral reaches to the fifth plate of the 

 dorsal scries, the ventral to the third abdominal plate. 



Very small round dots are visible on the head, on the back, and on 

 the sides ; the spines and rays of the dorsal fins are dotted mth brown. 



inches, lines. 



Total length 10 



Length of the head 4 3 



Width of the head between the orbits .... 6| 



Entire length of the snout 2 8 



Length of the praeorbital process 1 2 



Diameter of the eye 6| 



Greatest length of an anterior ventral plate. 1 1 



width of an anterior ventral plate. 9 



length of the middle ventral plate. 7 



width of the middle ventral plate . 8 



length of a posterior ventral plate. 4 



width of a posterior ventral plate . 7 



49. DACTYLOPTERUS. 



Dactylopterus, Lacep. iii. p. 325 ; Cuv. ^ Val. iv. p. 114. 



Head parallelopiped, with the upper surface and the sides entirely 

 bony ; scapula and angle of the proeoperculum produced into long 

 spines ; body with scales, strongly keeled, fvnd of moderate size ; 

 lateral line none. Two dorsals, the second not much longer than the 

 first ; pectoral very long (orgaii for Jlyinr/), vjith the lower portion de- 

 tached and shorter. Granular teeth in the jaws, none on the palate. 

 Air-bladder divided into two lateral parts, each with a large muscle ; 

 pyloric appendages in increased number. 



Mediterranean ; Atlantic ; Indian Ocean and Archipelago. 



1. Dactylopterus volitans. 



Aristot. iv. c. 9 ; 0pp. ii. v. 457-461 ; jElian. ii. c. 5 ; Athen. vii. 



p.m. 324; Bellon. p. 195; Rondel, pp. 284, 285; Salv. I 184; 



Wilhighby, p. 283 ; Parra, p. 25. pi. 14 ; Marcyr. Iter Bms. p. 102 ; 



Kleiti, 3Iiss. iv. pi. 14. f. 1, 2 ; Seba, iii. 28. 7 ; Leyuat, Voy. i. pp. 10, 



11. f. A & C. 

 Trigla volitans, L. Gni. p. 1346 ; Bl. taf. 351 ; Bl. Schn. p. 12. 



sp., Gronov. Zoophyl. no. 285. 



tentabunda, Walbanm, Art. Renov. iii. p. 362, note. 



fasciata, Bl. Schn. p. 16. tab. 3. f. 1. 



