554 PROCEEDINGS OF THE NATIONAL MUSEUM. vol.49. 



When a Cardisoma digs he makes frequent use of his great claws, 

 and in this respect differs from the fiddler crabs (Pearse, '12) which 

 Hve on the same mud flats with him. He may dig up a lump of dirt 

 with his chelipeds or gouge it out of the ground with the walking legs 

 of one side, like a fiddler. Dirt while being carried from a burrow is 

 hugged against the body by either chela and the walking leg next to 

 it or held in both chelae, like a washerwoman carrying an armful of 

 clothes. Burrows were closed by pushing up soft mud from the inside, 

 thus shutting the owner in. 



The holes were often dug at the bases of trees or under stumps, but 

 many were scattered over the open flats. They went down to water 

 or soft mud. 



Cardisomas keep themselves clean. After carrying a load they rub 

 their chelae together and scrape themselves with the legs. The eye- 

 stalks are wiped with the maxiUipeds. 



In fightmg the males use the great claws after the manner of fiddler 

 crabs. Combats were often seen. 



Cardisoma guanhumi is found in the Bahamas, and from Florida 

 Keys to Brazil. 



GECARCINUS LATERALIS (Freminville). 



Loose carapaces and claws were found at Punta Gruesa, but the 

 only living specimens were seen on the ocean beach at the mouth of 

 the Manzanares River. A male and a female were collected on the 

 night of August 27. One of these was at the bottom of a burrow 6 

 inches deep on the sandy beach. Another female was taken two days 

 later about 500 meters from the river at the edge of a rock slide in the 

 cactus brush. This individual had established herself under a rock, 

 where she had made a shaUow excavation. The male measured 37.2 

 mm. long by 49.2 mm. wide; the larger female, 34.5 by 44 nun. This 

 species ranges from the Bermudas, Bahamas, and Florida Keys to 

 Colombia and Venezuela. 



UCA MORDAX (Smith), 



Common in holes in the clay flat at the mouth of the Manzanares 

 River, where it associated with Cardisoma guanTiumi, and at Punta 

 Gruesa in holes in sand, under logs, and among mangrove roots. On 

 August 29 a female carrying eggs was captured at the first locality 

 mentioned. Thirty-five specimens were preserved. The largest male 

 measures 12.5 by 18.8 mm.; the largest female, 10.2 by 14 mm. 

 Range, from the Bahamas and West Indies to Rio de Janeiro. 



UCA MINAX (Le Conte). 



Abundant in the mangroves at Punta Gruesa. Eighteen specimens 

 were taken. Size of largest male, 20.5 by 29.8 mm.; female, 16.1 by 

 22.8 mm. Range (Smith, 70), Connecticut to Florida, and (now) 

 Colombia. 



