TALOKCHESTIA 167 



TALORCHESTIA. (Beach-Flea.) 



These active little animals inhabit sand beaches, where they 

 burrow in the sand and hide in the decaying vegetable matter 

 that accumulates along such beaches near high-water mark. 

 Turn over some of this material and notice the activity of the 

 animals that are disturbed. Most of them probably belong to 

 another closely related genus, but their movements are much 

 the same. How far can a specimen leap? Are the leaps of an 

 individual continuously in one direction, so it may get away 

 from the point of danger ? Is each leap straight forward or does 

 the animal whirl in the air? What purpose may be served by 

 the leaping? Try to catch a specimen. Determine how the 

 leaping is accomplished. Determine how the specimens burrow. 



If you will walk along a beach some quiet night with a lan- 

 tern you will probably see something of the night activities of 

 these animals. 



1. Select a large specimen and count the number of segments. 

 Is the body divisible into head, thorax, and abdomen? 



2. The eyes are not stalked. Are they compound? 



3. The second antenna of the male are very large. Compare 

 them with the first antennae and with the antennas of a female. 



4. Around the mouth are the labrum, forming an upper lip, 

 the first maxillipeds (fused), forming a lower lip, and between 

 them the mandibles, first maxillce, and second maxillae. 



5. Examine the appendages behind the mouth. How many 

 are there? How many bear claws? Compare these claws with 

 those of a lobster, and see how they differ. Which appendages 

 are used in crawling? Why are some of the appendages arranged 

 so they can be twisted around by the sides of the animal ? What 

 are the remaining appendages used for? 



6. Spread the appendages apart and find the gills, which are 

 attached to the bases of the appendages. 



Make a drawing of the animal. 



Smallwood: The Beach Flea: Talorchestia longicornis. Cold Spring Har- 

 bor Monogr., 1, 1903. 



