SEA WOODLOUSE. 155 



never seen it spontaneously in the water ; and those 

 which I have captured on the rocks, and transferred to 

 an aquarium, have died after a very brief interval. They 

 have little agility under any circumstances, and trust 

 rather to craft than to power for their safety. When 

 alarmed, they instantly gather in their feet, and drop 

 from their hold ; and, as I have said that the positions 

 in which they are found are for the most part perpendi- 

 cular surfaces, such as cliffs and sea-walls, their one 

 trick is often successful. 



Thus the Ligia makes a decided approach to an aerial 

 or terrestrial mode of life ; which, indeed, is strictly the 

 habit of some species with which every cultivator of 

 flowers is only too familiar. I refer to the little Wood- 

 lice, or Buttons, or Sows, as they are variously called, 

 so abundant in gardens, especially in pits and frames, 

 and so annoying for their depredations on our cherished 

 plants. These garden pests are scarcely to be distin- 

 guished as to their structure from the semi-marine 

 Ligia, particularly those flatter and softer species (Por- 

 cellio), which do not roll their body into a complete ball. 



In all these creatures we find maternal care. The 

 females carry their eggs in a sort of pouch or sac, placed 

 beneath the breast, which opens when these are hatched 

 to afford exit for the infant progeny. These have from 

 the first the same form and appearance as the adult, 

 except that they have at first six pairs of feet instead 



