NOTES ON COPEPODA FROM FIRTH OF FORTH 93 



variety of Longipedia were observed after the above Notes 

 had been prepared. This variety agrees in size and with the 

 detailed figures and description of Longipedia coronata in Dr. 

 Geisbrecht's work on the free-living Copepoda of Kiel 

 Fohrde, but differs from the description and figures of the 

 " male " in " British Copepoda," and from Longipedia coronata, 

 partially described and figured in the present Notes, in the 

 following particulars, viz : 



(1st) In the armature of the first pair of swimming-feet 

 being more slender ; (2nd) in the outer branches of the second 

 pair being proportionally longer. The two first joints of the 

 outer branch are about equal in length to the two first joints 

 of the inner one, and the large spiniform seta on the outer 

 edge of the long third joint of the inner branch has a position 

 nearly intermediate between the two smaller setae on the inner 

 edge; and (3rd) the middle lamellae of the fifth pairof feet in the 

 female are much narrower and more elongate. These differ- 

 ences, so far as we can make out, appear to be constant. For 

 the purpose of provisionally distinguishing this variety, we 

 propose to call it variety minor. Length of variety, '85 mm. 

 (^th of an inch). On the other hand, the form partially 

 described here as Longipedia coronata (type) agrees practic- 

 ally in size and in structure with the so-called " male " of 

 Longipedia described in "British Copepoda " and in " Die frei- 

 lebenden Copepoden," while that described here as Canuella 

 perplexa agrees in structure with the so-called " female " of 

 Longipedia in " British Copepoda." We have not seen Boeck's 

 description, and are unable to say which of the forms now 

 referred to agrees with that described by him. 



(b) In 1867 M. Hesse recorded 1 a new Copepod (Sittia- 

 ristes pagurt) living as a commensal in the same shell with 

 Pagurus (a kind of hermit-crab), and which in some respects 

 agrees with the form described by us here as Canuella perplexa, 

 but differs from it in the following important points. The 

 first abdominal segment in the female is " aussi long que les 

 quatre autrcs ; il est separe* du thorax par un espace assez 

 ecarte et arrondi qui facilite les mouvements du corps," and 

 each of the two ovisacs " forment un ovale tres-allonge et 



1 "Aim. Sc. Nat (Z00L ," 5th series, vol. vii. p. 205, Plate tV. Figs. 11- 



25 ; also op. cit. l». 211. 



