62 DR. H. J. HANSEN ON CRUSTACEANS [Jan. 20, 
all other species hitherto known by possessing an enormous multitude 
of luminous organs arranged regularly on the lower surface and 
near the lower lateral margins of the cephalothorax, on the six 
abdominal segments (figs. 2d, 7, &), on the sides of the shield 
(fig. 2a), and on all the appendages preserved (figs. 2c, d,e, f, g, h) 
with exception of the maxillule and maxille. The organs are 
easily seen; they look almost similar to the eyes in Aranee, and 
they differ much in size and direction. I have deemed it advisable 
to deal with the special arrangement and the structure of these 
organs in a separate section of this paper. 
SERG. DORSISPINALIS Bate, p. 394, pl. lxxil. fig. 1. 
Bate does not state directly the number of specimens, but he 
had probably only one. The length is “9 mm.” and the locality 
“south of Australia, March 1874.” An animal with a label of 
exactly the same contents was preserved in a microscopical pre- 
paration. It isa Mastagopus related to S. arcticus Kr., S. similis, 
n. sp., &e., but it could not be referred to any adult form. In 
the preparation the abdomen is seen from the side, and the 
cephalothorax essentially from below; the spine on the scutum 
on which Bate writes “just anterior to the [cervical] suture, in 
the median dorsal line, is a small, anteriorly directed tooth,” is 
in reality the gastro-hepatic spine, which besides has been drawn 
in a position too remote from the front. Bate’s figure is not 
correct in some other respects: in the antenn. ped. the second 
joint is about as long as the third, and both together somewhat 
shorter than the first; the eyes reach to the end of the first joint ; 
the squama is longer than in the figure, reaching almost beyond 
the second joint of the antenn. ped. and distally narrow; the ext. 
br. of urp. is a little longer and conspicuously more narrow than 
in the figure, while its marginal tooth is indicated correctly. 
SERG. LATERODENTATUS Bate, p. 395 (no figure). 
Bate has examined one specimen, measuring 8 mm. in length, 
and captured “ south of Australia, March 1874.” The type could 
not be found in the Museum. According to the description it is 
a Mastigopus belonging to the arcticus-group, probably a younger 
stage of the same species as that to which the preceding larva, 
S. dorsispinalis Bate, belongs. 
SuRG, NASIDENTATUS Bate, p. 398, pl. Ixxn. fig. 2. 
Bate does not state directly the number of specimens, and 
presumably he had only one; the length was 10 mm. and the 
locality the Pacific Ocean, between Valparaiso and Juan Fernandez. 
The type does not exist in the Museum. The species is a 
Mastigopus ; in wy earlier paper I had already referred it to the 
same group as S. arcticus, and nothing further can now be added. 
Sura. prapontius Bate, p. 399, pl. lxxil. fig. 3. 
Bate does not state the number of specimens, but presumably 
