CRUSTACEA OF ALABAMA. 25 



the dorsal margin and scattered throughout the shell. A dark blue or almost black spot 

 near the dorsal side and forward half of the shell indicates the position of the eye. The 

 first antennae, situated just in front of the eye, consist of seven joints ; on the middle of 

 the first joint is a short sensory filament ; at its juncture with the second joint are three 

 more. The fourth and fifth joints each bear four almost equal filaments. The sixth and 

 seventh joints each bear three unequal filaments ; all are plumose. 



The second antennae, situated just below the first, have five joints, the second joint 

 with one long filament and a small sensory filament ; about the distal quarter, from the 

 body, of the third joint are six filaments, five of which are of equal length, much plumose ; 

 on the sixth a short one found on the outside, not plumose ; on the inner side and near the 

 junction is one long, thick filament. In the middle of the fourth joint are four short and 

 one somewhat longer filaments ; at the junction with the fifth are four unequal barbed 

 filaments. The fifth joint, also, ends in four unequal barbed filaments. 



At the base of the second antennae is situated the mouth surrounded by the labrum 

 which forms the roof. This is divided into two parts, the basal or that part inserted in the 

 body, and the distal part or movable lip. The distal portion is divided into four plates, 

 two lateral and two medial. The lateral plates are slightly fringed and at the distal end 

 are divided to give room for the two medial plates, which bear upon their inner side two 

 small barbed hooks, each provided with a fringed plate. (See fig. 1, plate 36, Brady's 

 Monograph of British Ostracoda.) Below this is a pair of powerful mandibles, armed at 

 the distal end with nine spine-like teeth, in the middle bearing a four-jointed palp. The 

 first joint of which bears a branchial plate and three or four plumose spines ; the second 

 joint at the distal end, seven filaments and one plumose spine ; the third joint on the dis- 

 tal third bears four long filaments and at the junction, four others; the fourth joint is 

 armed with three somewhat long claws. Two pairs of maxillae ; the first large and di- 

 vided into four digital branches, the anterior branch being larger than the rest and two- 

 jointed ; attached to this is a large branchial plate. The second maxillae are smaller, 

 conforming strictly to the generic types, the distal end bearing about ten short spines and 

 and an appendage armed with two long and one somewhat shorter spines ; at its middle 

 also provided with a branchial plate. Two pairs of feet ; the first stout and five-jointed, 

 terminated by a long, curved claw, bearing upon each joint a single filament. At the 

 base of the claw are two short spines, one on each side. 



The second pair more slender and usually bent upwards within the valves ; each is 

 terminated by a short; stout, curved claw, and two filaments of about the same length ; 

 the third joint bears three short filaments, one at the base and one in the middle, and 

 one at the distal end ; the fourth joint has but one, found at the distal end. 



The post-abdomen forms two long, movable rami, which are well developed and ter- 

 minated by two claws of unequal length, and in fine specimens are serrated on their inner 

 edge toward the apex. The rami themselves are also serrated. The short seta on the 

 inner margin of the ramus is not far removed from the claws. The eye is single and 

 simple, marked by a black spot on the dorsal forward half of the body. The alimentary 

 canal is composed of only two pouches, the first forming the stomach, the second the in- 

 testine ; these lie near the dorsal side. 



In the female the ovaries are situated just beneath the shell, while the mucilage 



