212 



LIFE BY THE SEASHORE. 



tail fins bear round auditory organs (o in Fig. 61), for My sis 

 has ears in its tail. The last five segments of the thorax 

 are more or less movable, not fused together as in shrimps. 

 All the Schizopods you are likely to find on the shore 

 belong to this family. It is divided into a great number of 

 sub-families, chiefly on account of the varying structure of 

 antennas and telson, and the sub-families contain numerous 

 genera, but it will be sufficient for our purpose to retain the 

 genus Mysis in its old sense. For further details reference 

 should be made to Canon Norman's papers (see books of 

 reference at end). 



If you have succeeded in laying out the thoracic limbs 



FIG. &1.A, head, and B, part of tail of Mysis. A shows 

 the eyes (e), the scale (s), and part of the flagellum of 

 the right antenna, and the two antennules (a). B shows 

 the telson (t)and the left terminal swimmeret, with the 

 ear (o) in the inner branch. After Bell. 



of Mysis flexuosa in a row, and demonstrating the other 

 characters of the family to your satisfaction, you will find 

 no further difficulty in studying its specific characters. 

 Besides the points already noted it is distinguished by the 

 following peculiarities. First, the length of the antennal 

 scale (s in Fig. 61). To see this clearly, float your dead 

 Mysis in water the lid of a white ointment jar makes a 

 good dissecting dish and observe under a lens. You will 

 then see clearly the antennae with their long flagella and 

 stout scales (s), and the shorter antennules (a), each with 

 a three-pointed stalk and two feelers. In Mysis flexuosa 

 you will find that the scale of the antennas is narrow and 

 very long, twice as long as the stalk of the antennules ; it 

 is without bristles (setae) on its outer margin, and that 

 margin terminates in a distinct spine ; all these points are 

 clearly shown in Fig. 61, A, which also shows the eyes (e). 



