MICHTHEIMYSIS, TALORCHESTIA 183 



accumulates along such beaches along high-water mark, 

 smaller animals of a closely related genus, Orchestia, may be 

 found. The movements of both species 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 leap- 

 ing is accomplished. Determine how the specimens burrow. 



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

 lantern you will probably see something of the night activi- 

 ties of these animals. 



1. Select a large specimen and count the number of seg- 

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



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



3. The second antennae of the male are very large. Com- 

 pare them with the first antennae and with the antennae 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 maxillae, 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? Some of the appendages 

 are arranged so they can be twisted around by the sides of 

 the animal. What is their function? What are the remain- 

 ing 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. 



Kunkel: The Arthrostraca of Connecticut. Conn. State Geol. and Nat. 



Hist. Survey, Bull. 26, 1918. 

 Smallwood: The Beach Flea: Talorchestia longicomis. Cold Spring 



Harbor Monogr., 1, 1903. 



