COLLECTED BY CAPTAIN TOYNBEE. 177 



distinctly six-jointed, — the anterior portion, including tlie base of the maxillipeds, being 

 separate from the five segments bearing the natatory feet. In some specimens, which in 

 other respects were like the remainder, the antennse were rather shorter than usual. It 

 would be very desirable to ascertain, by the examination of a number of specimens, how 

 much variation exists in this character. Prof. Dana describes the two posterior subapical 

 setEB of the anterior antennge as " subequal ;" in aU my specimens the antepenultimate 

 seta was distinctly the larger of the two. 



According to Mr. Toynbee's notes, his specimens had red antennse and feet ; while Prof. 

 Dana's were of a faint purplish-blue colour. 



Of two specimens which were captured on the 15th of December 1858, each had two 

 spermatic tubes attached to the posterior part of the cephalothorax. The specimens in 

 question had the segments of the abdomen gradually decreasing in length, the basal being 

 at least half as long again as the second segment. 

 This species was met with on several occasions. 

 Collected October 25. S. lat. 13° 43' ; W. long. 33° 55'. 



„ November 4. S. lat. 33° 27' ; W. long. 30° 28'. 



„ November 22. S. lat. 40'' 53' ; E. long. 45° 22'. 



„ December 14. S. lat. 5° 49'; E. long. 83° 17'. 



** Cephalothorax sttperne visits postice actdus, angulis posticis iion appressis. 



Calanus brevicornis, Lbk. 



This species may at once be distinguished from Calamis settiligerus, which it otherwise 

 much resembles, by the shortness of the antennse, and by the front being produced in 

 front of the stylets and of the base of the antennse. The cephalothorax was five-jointed 

 in my previous specimens ; in the present individuals it had six segments — an important 

 variation, which appears also to occur- in C. setuligerus. 

 Collected November 22, 1858. S. lat. 40° 53'; E. long. 45° 22', 

 „ „ S. lat. 0° 30'; W. long. 0° 30'. 



Calanus communis, Dana. 



Collected October 7th. N. lat. 7° 15' ; W. long. 27° 2'. 

 „ June 22nd. S. lat. 0° 40' ; W. long. 0° 20'. 



Calanus vulgaris, n. s. Prons rotundatus. Cephalothorax 5-articulatus, superne visus 



angulis posticis acutis, non appressis; latere visus rotundatus, inermis. Antennse 



anticse corpore paulo breviores, setis apicalibus brevibus, antica penultima elongate, 



postica penultima antepenultimaque longioribus subsequis. Abdomen 4-articulatum, 



stylis caudalibus brevibus, setis mediocribus, secundis longioribus. 



In general outline, in the proportion of the cephalothoracic and abdominal segments, 



and in the setse of the anterior antenna?, this species very closely resembles C. commm/is, 



from which, however, it differs in the relative shortness of the antennse, and in having the 



cephalothorax unarmed behind. It is true that Dana makes no mention of the lateral 



cephalothoracic hook ; but it was present in all the specunens examined by me which 



possessed the other characters of the species. 



