218 LIFE BY THE SEASHORE. 



of about three-quarters of an inch, and is usually olive- 

 green in colour, minutely speckled with black spots. The 

 inferior antennas, or antenna? proper, are shorter and stouter 

 than the superior, and the last pair of jumping legs are 

 furnished with hooks. 



Before leaving the Amphipods one other set of forms 

 must be noticed. These, typically represented by the 

 species of Caprella, are very different from the rest, being 

 both curious and beautiful, but unfortunately not very 

 abundant or very easy to find. Study closely a rock pool 

 lined with red seaweed, and you may see a slender thread- 

 like creature, probably rather over half an inch in length, 

 which attaches itself to the weed by its long back legs, and 

 sways back and forwards in the water. The tint is exactly 

 that of the weed, and the swaying motion so similar to that 

 produced by currents of water, that it is exceedingly 

 difficult to distinguish the little organism. Disturb it, and 

 it will swim rapidly through the water by suddenly con- 

 tracting and straightening the body, or travel over the 

 surface of the weed by alternately fixing the opposite ends 

 of the body like a "looping caterpillar." It is unfortunate 

 that we have no common English name for these interesting 

 and curious little creatures. One or two should be taken 



home for careful exam- 

 ination under a lens. 

 It will then be found 

 that the second thoracic 

 segment is fused to the 

 head as well as the 

 first, so that there are 

 only six free segments. 

 In the figure the first 

 and sixth are num- 

 bered. The abdomen 



Fio. 64. Caprella Unearis. The letters are (ttb) is greatly reduced, 

 explained in the text. and at most bearg mQTQ 



rudiments of appendages. The head bears two pairs of 

 similar antennae, and on account of the fusion of segments 

 the first pair of legs appears to arise from it. The second 

 pair of legs is large and sub-chelate, as in some shrimps 

 that is, the last segment can be bent down on the second 



