300 SMITHSONIAN MISCELLANEOUS COLLECTIONS [vOL. 45 



backward; the ventrals are also extended downward and touch the 

 bottom quite lightly. The body rests nearly parallel with the ground, 

 and the caudal is somewhat upraised from the bottom, and the pec- 

 torals and ventrals can be used as props for the body. Heckel and 

 Kner have remarked of the European species, that even when the 

 fish remains still or floats, the last three or four rays of the very erect 

 dorsal are alone in a constantly oscillating motion. And, strange to 

 say, they add, the fishes remain thus at rest often for hours at a 

 time, now in a horizontal, now in a vertical position, with the head 

 turned either upward or downward. Then suddenly they all dart 

 from the bottom to the surface with a quick movement of the tail, 

 gasp for air, emit it again in diving as large bubbles through the 

 gill-opening, and for some time afterward breathe very slowly. 

 Heckel and Kner also remarked on their peculiar movements when 

 swimming. The pectorals and ventrals are moved alternately, like 

 the feet of a dog running, and the dorsal makes a quick wavy motion 

 with all its rays, the like of which is seen in seahorses and pipe- 

 fishes {Hippocampus and Syngnathus) , which is effected by a pecu- 

 liar disposition of individual muscles for the various rays of the fin. 

 But most of their life is spent at the bottom, and when a clear 

 pool reveals no evidence of their existence, a little stirring up of the 

 bottom may bring many to view. " On disturbing them, occasionally, 

 instead of swimming, especially if the water is very shallow, they 

 make a forward movement, by giving these fins a leg-like motion, 

 indicated by leaving faint traces, thus: \''W\ upon the sand." 

 But it is also " often a voluntary movement on their part," 

 and, in fact, " if suddenly disturbed, they generally dart off by 

 swimming only, and bury themselves, tail-foremost, in the mud." 

 They are perfectly at home there and Abbott claims that they " can 

 pass through soft mud with as much ease [not quite!] as other 

 fishes do through the clear waters." They are mostly carnivorous 

 and do not appear to manifest any special preference for anything 

 that is of the flesh, but their capacity is limited by their own size and 

 that of their mouth. In a state of nature, they feed largely upon the 

 aquatic larvse of insects as well as crustaceans, and the eggs of fishes 

 as well as young and small fishes. They also make excursions from 

 the water in search of insects. " Unlike any other of our fishes," 

 Abbott asserted, " the mud-minnow will leap twice and thrice its 

 length above the surface of the water to seize a fly or beetle that 

 happens to rest upon some overhanging blade of grass or twig." 

 But, although mostly carnivorous, they are not entirely so, as has 

 been asserted. Forbes (1883), indeed, found that, in the "mud 



