CLASSIFICATION OF THE MAIOID CRUSTACEA. 673 



Fig, 7. Maia squinado, Linn. Dorsal view of the front of the cephalothorax, 

 showing the form of the upper orbital wall, which is formed of long 

 spines, beneath which the long and slender eye-peduncles are retrac- 

 tile ; natural size. 



8. Inferior view of the same, showing the form of the inferior margin of 



the orbit and of the enlarged basal antennal joint ; natural size. 



9. Pisa {Arciopsis) Icmata, Lamk. Dorsal view of the front of the cephalo- 



thorax, showing the narrow hiatus in the upper orbital margin and 

 the short eye-peduncle; X 2 diam. 

 10. Inferior view of the same, showing the hiatus in the lower orbital 

 margin and the basal antennal joint; X 2 diam. 



Plate XIII. 



Fig. 1. Micippa cristata, Leach. Inferior view of the front of the cephalo- 

 thorax, showing the deflexed rostrum, greatly dilated basal antennal 

 joint, and nearly complete orbits; natural size. 



2. Lateral view of the orbit and deflexed rostrum ; natural size. 



3. Criocarcinus superciliosiis (Herbst). Inferior view of the front of the 



cephalothoi-ax, wherein the posterior part of the orbit is represented 

 only by the postocular spine, and the anterior part surrounds the 

 laterally projecting eye-peduncle in the form of a tube open below ; 

 natural size. 



4. Pericera cornuta, Latreille. Inferior view of the front of the cepha- 



lothorax, showing the short epistome and greatly-developed basal an- 

 tennal joint ; natural size. 



5. Lateral view of the orbital cavity (the eye-peduncle being removed) 



showing its circular form and complete margin ; natural size. 



6. Othonia aculeata (Gibbes). Inferior view of front of cephalothorax, 



showing the extreme development of the basal antennal joint (which 

 has coalesced with the surrounding parts), the dilated second an- 

 tennal joint, and obsolescent rostrum ; X 1^ diam. 



7. Mithrax hispidus, Herbst. Dorsal view of the front of the cephalo- 



thorax, showing the foi'ni of the rostrum and orbits ; natural size. 



8. Inferior view of the same, showing the form of the epistome and basal 



antennal joint ; natural size. 



9. Lamhrus macroclielos, Herbst. Inferior view of the front of the cepha- 



lothorax, showing the small antennas inserted in the hiatus between 

 the inner orbital angle and the front ; X 2 diam. 



10. (Ethra scruposa (Linn.), Similar view of the front of the cephalothorax ; 

 natural size. 



11. Harrovia albolineata, Ad. & White. Similar view of the front of the 

 cephalothorax ; X 3 diam. 



