ELIOJ- : NUDIBRANCHS FROM THE INnO-PACIFIC. 83 



purplish. On the labial cuticle is a greyish armature composed of 

 small rods, slightly bent; it is very faint and shadowy, but still a 

 definite armature, and not merely scattered rods. The radula con- 

 sists of thirty to thirty-five rows, containing from 120 to 150 teeth on 

 either side of a rather broad rhachis. There is no central tooth. The 

 innermost teeth are low and broad, with a prominence on the inner 

 side, bearing about five denticles. On the outer side are five to six 

 rather irregular denticles. The second tooth is also rather low, but 

 has no denticles on the innerside ; the denticles on the outerside 

 are strong, but set rather low down. The teeth become gradually 

 taller, and have denticulations higher up the shaft, until the definite 

 form is attained about the fifth tooth ; after this the teeth have long 

 and rather wavy bases and a slender shaft, hamate, but very erect. 

 From many points of view they look smooth, but all are denticulate 

 on the outer side ; the denticles are as many as eighteen, but are 

 sometimes very faint. The teeth increase gradually in size until 

 almost the end of the row. The two or three outermost are 

 shorter and degraded, with a wavy or spoon-like outline, but not 

 denticulate on the top. The salivary glands are large flat bands, 

 which enter the buccal mass without contracting into a thin duct. 

 Their distal ends are expanded and foliaceous. 



The central nervous system is with difficulty separable from its 

 capsule and from the blood-gland which adheres to its upper sur- 

 face. The main portion forms a continuous yellow mass, not divided 

 into distinct ganglia, though the cerebro-pleural and pedal parts are 

 indicated by lobes. The eyes are sessile. The common commissure 

 is thick and short. The cerebro-buccal connectives are longer and 

 thinner. The buccal ganglia are round and connected by a short 

 commissure ; the gastro-oesophageal ganglia are elliptical. 



The oesophagus is thm. The small stomach is entirely enclosed 

 in the dark-brown liver. The intestine issues about the middle of 

 the liver, runs forward and then backward. The hermaphrodite gland 

 forms a thin whitish layer — sometimes merely a dendritic pattern — 

 on the surface of the liver. Its ampulla is long and bent two or three 

 times on itself. On the male branch is a large prostrate gland, 

 roughly triangular, and bent on itself, so as to appear bilobed ; from 

 it issues the very long, much coiled vas deferens, consisting of two 

 parts : the upper, comparatively thick and large ; the lower, which 

 terminates in the verge, thin and muscular. This lower portion and 

 the verge are armed with thick-set spines, which have a stout base, 

 from which rises a thinner apex, sometimes irregularly bent. The 

 spermatotheca is large, with thin walls, and apparently of globular 

 shape, but it is indented and broken in most specimens, and the 

 contents are not compact. The spermatocyst is much smaller, ellip- 



