upright position in the water, propelling itself 

 with the aid of its single dorsal fin situated on the 

 back about the middle of the body, vibrating this 

 appendage with a rapid undulatory motion. But 

 for the most part, the hippocampid remains sta- 

 tionary, shifting about only when such occasions 

 as the demands of love or hunger require. From 

 dangerous enemies, it seldom essays to flee. In 

 threatening circumstances, it relies for protection 

 solely on its inconspicuous appearance. Grotesque 

 and fantastic as it may appear to human eyes, it 

 is in this very bizarrerie that lies its safety from 

 the assaults of natural foes. The numerous fila- 

 ments and tubercles on its body doubtless do much 

 to help it simulate the weedy growths which it 

 inhabits, but it is further enabled to identify itself 

 with its surroundings by a certain capacity to con- 

 form with the prevailing color of those surround- 

 ings. Although normally dark — almost black — it 

 can, to some extent, change its hue. Thus, with 

 these natural advantages, together with its habit 

 of remaining for the most part immobile, it easily 

 escapes the casual view. 



Yet, despite the fact that the sea-horse is slow- 

 moving, it is largely a predatory animal. Now, 



[278] 



