94 - ANNALS OF SCOTTISH NATURAL HISTORY 
sont presque pointus des deux bouts. [Ils sont attachés, par 
leur extrémité supérieure et par un pédicule, au bord inférieur 
du dernier anneau thoracique, et leur longueur égale celle de 
abdomen.” There also appear to be important differences 
in the structure of the mouth appendages and swimming-feet 
in both sexes. Swmzaristes is also much longer than our species, 
being “5 millimetres de long” (? including tail sete). The 
habitat is quite different, for the Swuarzstes “sont les com- 
pagnons intimes des Pagures, et c’est avec la plus grande 
peine qu’on peut les en séparer, non qu ils soient fixés sur eux 
comme le sont leurs parasites, mais par leur adresse a se 
cacher dans Vintérieur, ou en dessous des coquilles que ceux- 
ci habitent.” 
In 1884 Dr. Wilh. Miiller described’ a large Copepod 
(Longipedina paguri) that he had discovered living with 
Pagurus bernhardus. This is considered by Dr. Canu to be 
the same as the Suznarzstes of M. Hesse; it also resembles, 
even more .closely than Sumaristes, the form now described 
by us. 7 
After a careful study of the descriptions and figures of 
— Sunaristes and Longifedina we find that, if both authors are 
correct, the difference in their descriptions and figures are 
scarcely reconcilable, and appear to refer to different species ; 
and further, the difference both in respect of structure and 
habitat between both of these and the species described by 
us is apparently so considerable that we prefer for the present 
to consider the Forth species as distinct from both. Canuella 
perplexa is, so far as we know, a free-living Copepod, and is not 
associated in any way whatever, as commensal or parasite, with 
any other animal. 
EXPLANATION OF PLATE. 
Canuella perplexa, gen. et sp. n. 
Rice snes Adult femalews e : : : x 46°6 
i HOouotsecondspalimmne ; x 2055 
ee Hoot on iith pair : x 760 
Longipedia coronata, Claus. 
Mew Adult female =F : . x 46°6 
PT 5e oot on secondspalr ae ; : x 84°0 
PUOu EH OOt On mini paltqntemiale alae ‘ : x 190 
1 «¢ Archiv fiir Naturgesch.” Jahrgang 50, Erste Band, p. 19, Plate III. 
