GAMMARUS. 



369 



m. 



= month. 



mnp 



. = mandibular palp. 



mn.i 



. = mandibular teeth. 



m.p. 



, = membrana propria. 



mxp 



. = maxilliped. 



n. - 



= nucleus. 



n' = 



= nucleolus. 



tl.G. 



= ventral nerve cord. 



OS. ■ 



= ostium. 



p. = 



= pericardium. 



p.c. 



= pericardial cavity. 



per. 



1 = first peraeopod. 



per. 



2 = second peraeopod. 



per. 



3 = third peraeopod. 



per. 



J t = fourth peraeopod. 



per. 



5 = fifth peraeopod. 



peri, 



n.r. = peri oesophageal 



nerve ring. 



v-g- 



3 = third pair of post- 



oesophageal nerve ganglia. 



pi. i 



' = first pleopod. 



pi. 2 = second pleopod. 



pi. 3 = third pleopod. 



.*. = sac-like dilation of mid- 

 gut. 



set.cut. = setigerous plates of 

 cuticle of stomach. 



set.cwtl. = setigerous plates of 

 cuticle at origin of hepato- 

 pancreatic tubes. 



st. = stomach. 



st.s. = sternal sinus. 



t. — tergum. 



tel. = telson. 



tr.br.v. = transverse branchial 



uro. 1 = first uropod. 

 uro. 2 = second uropod. 

 uro. 3 = third uropod. 

 v. = valve separating heart 

 from posterior aorta. 



Plate I. 



Fig". 1. First antenna, with four- jointed secondary 

 fiagellum (/?. sec.) or exopodite. 



Fig. 2. Second antenna, with enlarged basal joint 

 bearing the antennary cone (ant. c.) and stout 

 fiagellum bearing plumose setse and calceoli 

 (calc). 



Fig'. 3. Xinth and tenth joints of second antenna (en- 

 larged) showing calceoli. 



Fig. 4. Left mandible, showing three-jointed mandi- 

 bular palp (mn. p-), and saw-like jaws bearing- 

 double rows of teeth. 



Fig. 5. Left first maxilla, also enlarged single spine. 



