364 REPORT OP NEW JERSEY STATE MUSEUM. 



Sub-Order ANOMURA. 



Abdomen in its entirety less well developed than cephalothorax, 

 though exceptionally elongate and extended in straight line 

 usually flexed on itself, or flexed against thoracic sternum, or 

 coiled in a spiral, in which last case more or less soft and asym- 

 metrical. Carapace traversed on either side in longitudinal or 

 obliquely longitudinal direction by distinct suture (linea ano- 

 murica) which marks off more or less sidewall of carapace from 

 dorsal and dorso-lateral region. Rostrum often ill-developed, 

 and often fails to cover ophthalmic somite completely. Last 

 thoracic somite independent and last thoracic sternum when not 

 atrophied separate and freely movable. In correspondence with 

 reduction of last thoracic somite, last pair of thoracic legs always 

 reduced in length. Sometimes an orbital notch, but eyes never 

 concealed in orbits. Antennular peduncle generally weak and 

 flexed, longer than flagella. Antennal scale, when present, an 

 "acicle" and never foliaceous. External maxillipeds commonly 

 pediform. First pair of legs well developed and chelate, second 

 and third pairs well developed and monodactylous, and either 

 fourth and fifth pairs both much reduced in size or if fifth pair 

 well developed as second and third, then fifth pair slender, weak 

 and folded. Epipodites much more often absent than present on 

 thoracic legs and second maxillipeds. Abdominal appendages 

 weak, and with tendency to become rudimentary or to disappear 

 on one or both sides. Genital ducts never open upon sternum. 

 Biranchise usually fourteen on each side, and also frequently de- 

 veloped as phyllobranchiae. 



This is a large group, embracing forms mostly in the deep seas. 

 They are usually divided in five groups or super-families, as the 

 Hippidea, Paguridca, Porcellanidea, Lithodea, and Galatheidea, 

 though only the first two are represented in our limits. The 

 second to last of these groups are bathyic, while the Hippidea 

 are littoral burrowing forms. 



Key to the super-families. 



a. Carapace ovate or partly quadrate, smooth ; abdomen usually firm, and 

 not especially long, symmetrical. hippidea 



aa. Carapace elongate and partly cylindrical, more or less roughened ; ab- 

 domen usually soft, long, coiled, rarely symmtrical. paguridea 



