THE SEA-SPIDER. 
439 
In the accompanying illustration of the Stenorhynchus may be seen one example of the 
first family of these animals, being a group of Crustaceans distinguished chiefly by the singular 
form of the carapax or upper shell, which is wide and abrupt at the base, but is prolonged in 
front, so as to form a long and pointed beak. In all these creatures the legs are long in com- 
parison to the body, but in the Leptopodia they are of such inordinate length, as to remind 
the observer of the round-bodied, long-legged harvest spider, which scuttles over the ground 
so rapidly when disturbed. On account of this great length of limb and small size of body, 
these crabs are often called Sea-spiders. The eyes of the Leptopodia are rather large, and not 
retractile. It may here be mentioned that the eyes of Crustacea bear some resemblance to 
those of insects, being compound organs, with a large number of facets, some square and some 
hexagonal. The eyes of the common shore crab or the shrimp afford excellent examples 
of this structure. It is a native of the West Indies. 
SEA-SPIDER .— Stenorhynchus longirostris. 
In the Stenorhynchus, the projecting beak is proportionately shorter than in the preceding 
genus, is cleft at the tips, and very sharp. The fore-limbs, which are furnished with large 
claws, are stout and strong. 
As the shelly armor of the Crustaceans is, in most cases, so hard, strong, and unyielding, 
the mode of growth might be considered a problem not very easy of solution. For with the 
Crustaceans the growth continues during nearly the whole of life, or at a]l events for several 
years after they have passed through the various changes to which they are subjected in their 
imperfect stages of existence. Their increase of size and weight is marvellously rapid, and 
how it can be accomplished without subjecting the Crustaceans to the lot of the starveling 
mouse, who crawled into a jar of corn, but could not crawl out again after feasting on its 
contents, seems to partake of the character of an animated puzzle. 
The answer to the problem is simply that the creature sheds its armor annually, expands 
rapidly while yet covered only by a soft skin, and is soon protected by a freshly -deposited 
coat of shelly substance. Even this answer contains a second problem little less difficult than 
