88 



South Australia, New Zealand, Falkland Islands, Mauritius, 

 Reunion, Cape of Good Hope, Tropical Atlantic, Brazil, West 

 Indies, Mediterranean. 



This species was first described from East India, from open 

 sea in floating seaweed, by Osbeck (Dagbok Resa Ostindien 

 i757> P- 305)- 



9. Syngnathus acus L. '). [Fig. 37, p. 89]. 



Syngiiathus aciis Linne, Syst. nat. ed. X. 1758, p, 337. 



Syngnathus acus Kaup, Cat. Lophobr. Fish, 1856, p. 41. 



Syngnathus hrachyrhynchjis Kaup, ibid. p. 42. 



Syngnathus acus Dumei'il, Hist. Nat. Poissons II. 1870, p. 552. 



Syngtiathus brachyrhynchtis Dumeril, ibid. p. 554. 



Syngnathus acus Giinther, Cat. Brit. Mus. VIII. 1870, p. 157. 



Syngnathus acus Sauvage, Hist. nat. Poiss. Madagascar 1891, p. 506. 



Syngnafhiis acus ]^.\.zo\\' Sc Lenz, Abh. Senckenb. naturf. Gesellsch. XXI. 1899, p. 529. 



D. 35— 45; P. 12— 14; A. 4; C. 10; Rings 18—19 + 38—44; 

 subdorsal rings 1+7 — 11 or 2 + 8. 



Trunk heptagonal, sometimes much deeper than head, ab- 

 dominal keel more or less pronounced; tail quadrangular. Shields 

 transversely striated, their edges conspicuous but smooth, 

 intermedial shields smooth. Superior cristae of trunk and tail 

 discontinuous, inferior cristae of trunk and tail continuous. 

 Median cristae of trunk and superior cristae of tail continuous 

 or nearly so, the former reaching to hindborder of last trunk 

 ring, the latter beginning slightly above it at the frontborder 

 of the first tailring. Head about 6'/^ to nearly 8 times in 

 total length, more or less than twice in trunk. Upper and 

 lateral surface of head strongly corrugated, occiput elevated 

 on its posterior border and provided with a low median keel, 

 which is continued on the strongly corrugated praenuchal and 

 nuchal shield. Eye somewhat more than 8 to 9 times in head, 

 more or less than 5 times in snout. Snout 1.5 to less than 

 twice in length of head ; it is equal to distance from frontborder 

 of eye to base or middle or even end of pectorals; postorbital 

 space 1.7 to 2.8 times in snout. Snout with a sharp median keel, 

 smooth, in older specimens slightly serrated, reaching to inter- 



i) We believe that Syngnathus Schlegeli Kaup (Cat Lophobr. Fish, 1856, 

 p. 46) is identical with S. acus L., but we presume that there are small racial 

 differences in the slenderness of the body, the length of the snout, the subcon- 

 tinuity or continuity of the median cristae of trunk and superior cristae of tail, 

 according to the locality of this widely spread species. 



