ENTOZOIC COPEPOD FROM JAPAN. 223 
side to the previous one. It is difficult to decide if the terminal 
papilla-like part is a distinct segment or only a portion of the 
second ; it is, however, quite free of spines or hooks, and it ends 
bluntly. 
There seems to be no stage between this and the adult form, 
nor can I find any stage earlier than this ; apparently there are 
but these two stages in the male. 
The adult organ possesses a very characteristic chelate organi- 
zation. There is a basal joint which, compared with the next 
seoment, is rather slender, and is directed forwards and outwards 
(Pl. 22. fig. 18); articulating with this is the main joint, large 
and strong, on the distal end of which the chele work. The 
chelz are composed of two parts—a pad (pd.) and a hinged 
beak (6%.); the protruding pad on which the beak bites is on the 
inner surface of the limb; at its base itis surrounded by a circlet 
of fine set; the moveable beak is hinged on in such a way as 
to close down on this pad, it being worked by powerful muscles. 
There are no set or spines on this appendage in the adult; it 
is essentially characteristic of the male, there being nothing 
comparable to it in the female. 
The two maxillipedes are so arranged that they slope forwards 
and inwards, almost meeting in the middle line (Pl. 21. fig. 3, mp.”), 
the chele thus working in front of the mouth-parts. The first 
and second joints are bent on each other, forming a very pro- 
nounced elbow, which points outwards, for the first segment 
slopes forwards and outwards, while the second slopes forwards 
and inwards, the angle between being about 60°. 
Close to the basal joint is the first maxillipede, which is con- 
siderably flatter in the adult than in the immature stage; in the 
adult it has the form of a very flat plate of chitin, with its 
rounded antero-lateral border fringed with sete. 
This appendage in Goidelia japonica differs fundamentally 
from the corresponding organ in Clausidium, as described by Claus 
and Canu. These authors show that in these cases (Clausidium, 
Hersiliodes, and Gardella) it is armed at the end with a powerful 
recurved spine in the male (Gardella), rather more reduced in 
Hersiliodes, yet in no instance is it a chelate structure as is here 
shown to be the case. According to Claus, there is a slight 
resemblance in Clausediwm, though even there nothing occurs of 
the nature of chelew, and tke basal joint has a stout seta, while 
there are numerous defensive weapons at the extremity: “an 
