7(54 NATURAL HISTORY OF AQUATIC ANIMALS. 



but its holes are usually much larger, often an inch or an inch and a half in diameter. It is much 

 less active than the ' Fiddlers,' but can pinch very powerfully with its large claws, which are 

 always promptly used when an opportunity occurs. 



"On the marshes farther up the estuaries, and along the mouths of rivers and brooks, and 

 extending up even to places where the water is quite fresh, another and much larger species of 

 'Fiddler Crab' occurs, often in abundance; this is the Gelasimus mincuc. It can be easily 

 distinguished by its much larger size and by having a patch of red at the joints of the legs. Its 

 habits have been carefully studied by Mr. T. M. P-raddeu, of New Haven, who has also investigated 

 its anatomy. According to Mr. Prudden, this species, like Gelasimus puyilator, is a vegetarian. 

 He often saw it engaged in scraping up and eating a minute green algoid plant which covers the 

 surface of the mud. The male uses its small claw exclusively in obtaining its food and conveying 

 it to the month. The female uses either of her small ones indifferently. In enlarging its burrows, 

 Mr. Prudden observed that these Crabs scraped off the mud from the inside of the burrow by 

 means of the claws of the ambulatory legs, and, having formed the mud into a pellet, pushed it up 

 out of the hole by means of the elbow-like joint at the base of the great claw, when this is folded 

 down. He also ascertained that this Crab often constructs a regular oven-like arch of mud over 

 the month of its burrow. This archway is horizontal, and large and long enough to contain the 

 Crab, who quietly sits in this curious doorway on the -lookout for his enemies of all kinds. 



" This species can live out of water and without food for many days. It can also live in 

 perfectly fresh water. One large male was kept in my laboratory in a glass jar, containing nothing 

 but a little siliceous sand moistened with pure, fresh water, for over six months. During this 

 whole period he seemed to be constantly in motion, walking round and round the jar and trying 

 to climb out. He was never observed to rest or appear tired, and after months of confinement and 

 starvation was just as pugnacious as ever. 



"Although some of the colonies of this species live nearly or quite up to fresh water, others 

 are found farther down on the marshes, where the water is quite brackish, and thus there is a 

 middle ground where this and G. pugnax occur together. This was found by Mr. Prudden to be 

 the case both on the marshes bordering West River and on those of Mill River, near New Haven. 

 They are abundant along both these streams. The holes made by this species are much larger 

 than those of G. pugnax. Some of them are from an inch and a half to two inches in diameter. 



" On sandy beaches near high-water mark, especially where the sand is rather compact and 

 somewhat sheltered, one of the ' Fiddler Crabs,' Gelasimus pugilator, is frequently found in great 

 numbers, either running actively about over the sand, or peering cautiously from their holes, 

 which are often thickly scattered over considerable areas. These holes are mostly from half an 

 inch to an inch in diameter, and a foot or more in depth, the upper part nearly perpendicular, 

 becoming horizontal below, with a chamber at the end. Mr. Smith, by lying perfectly still for 

 some time on the sand, succeeded in witnessing their mode of digging. In doing this they drag 

 up pellets of moist sand, which they carry under the three anterior ambulatory legs that are on 

 the rear side, climbing out of their burrows by means of the legs of the side in front, aided by the 

 posterior leg of the other side. After arriving at the mouth of their burrows and taking a cautious 

 survey of the landscape, they run quickly to the distance often of four or five feet from the burrow 

 before dropping their load, using the same legs as before and carrying the dirt in the same 

 manner. They then take another careful survey of the surroundings, run nimbly back to the 

 hole, and after again turning their pedunculated eyes in every direction suddenly disappear, soon 

 to reappear with another load. They work in this way both in the night and in the brightest 

 sunshine, whenever the tide is out and the weather is suitable. In coming out or going into their 



