Even in the closely-related lobster (Homarus) the mid-gut may be 2 or 3 in.
There is every reason to believe 2, Gastric teeth of common that, in the primitive Arthropoda, lobster, Homarus vulgaris.
When the eye-stalk is removed from a living lobster or prawn, it is found that under certain conditions a many-jointed appendage like the flagellum of an antennule or antenna may grow in its place.
Giesbrecht, displacing the older name Ascomyzontidae, assigns to this family 21 genera in five subfamilies, and suggests that the long-known but still puzzling Nicothoe from the gills of the lobster might be placed in an additional subfamily, or be made the representative of a closely related family.
Many of the larger species of Crustacea are used as food by man, the most valuable being the lobster, which is caught in large quantities on both sides of the North Altantic. Perhaps the most important of all Crustacea, however, with respect to the part which they play in the economy of nature, are the minute pelagic Copepoda, of which incalculable myriads form an important constituent of the " plankton " in all the seas of the globe.