35 



2. Superior cristac of trunk and tail discon'Linuous, 

 a. Operculum without a keel. Anus in or before 

 middle of length. 

 X. Dorsal 42 — 60. Subdorsal rings 4 — 5 -\- 8 — 9. 



Snout distinctly separated from forehead. . . Coelonoliis p. 56. 

 /3. Dorsal 64 — 68. Subdorsal rings 11 — 12 ■\- 4. 

 Upper profile of snout gradually continued in 



that of forehead Belonichthys p. 59. 



/'. Operculum with a complete or basal incom- 

 plete keel. ( 

 x. Trunkrings more numerous thantailrings. Anus 

 l)ehind middle of length. Dorsal for its greatest 

 part inserted on trunk ; caudal longer than 



half length of head Doryi-haniphus p. 63. 



^. Trunkrings equal to or generally less numerous 

 than tailrings. Dorsal for its greatest part in- 

 serted on tail ; caudal equal to or shorter than 

 postorbital part of head. 



ux. Anus behind middle of length. Number of 

 trunkrings equal to or somewhat less than 

 that of tailrings. Snout longer than remain- 

 ing part of head Mkropliis p. 43. 



|9|3. Anus generally before middle of length. 

 Number of trunkrings less than that of 

 tailrings. Snout shorter or only slightly 



longer than remaining part of head . . . Dorylchtliys p. 49. 

 II. Brood organ subcaudal {Urophori Duncker). 



A. Eggs attached to and isolated by the skin of the 

 ventral surface of the anterior part of the tail, open, 

 not protected by lateral cutaneous folds or bony 

 plates (^Sole/iogiiaihi/ia Duncker). 



I. Tail prehensile. Dorsal situated on tail only. Oper- 

 culum without keel but with smooth or serrated 

 radial ridges Soleguathus p. 65. 



B. Eggs attached to and isolated by the skin of the 

 ventral surface of the anterior part of the tail; late- 

 rally protected by osseous plates or cutaneous folds 

 only, which coalesce during breeding. {Syngnathina 

 Duncker). 



1. Dorsal, anal and pectorals absent Penetopteryx p. 95. 



2. Pectorals absent Nannocainpus p. 94. 



3. Dorsal, anal and pectorals present. 

 a. Caudal fin none. 



