1914.1 NATURAL SCIENCES OF PHILADELPHIA. 41 



also in collections from Lake Winnepesaukee made during July and' 

 August, 1909. 



Subgenus MICROCYCLOPS Glaus. 

 Cyclops varioans Sars. PI. Ill, figs. 6-10. 



Cyclops varicans Sars, '62, pp. 252, 253. 



Cyclops varicans Schmeil, '91, pp. 33, 34; '92, pp. 116-118, pi. VI, figs. 1-5.. 



Cyclops varicans Forbes, '97, pp. 63 and 64. 



Cyclops varicajis Lilljeborg, '01, pi. IV, fig.s. 23, 24, pp. 72-74. 



Cyclops riibelhis Lilljeborg, '01, pi. IV, figs. 25 and 26, pp. 75-77. 



Cyclops bicolor Byrnes, '09, pi. XIII, pp. 29-31. 



Synonymy and Distribution. — Though I am unable to translate 

 Lilljeborg's Swedish description of his new species C. rubellus, I am 

 convinced from the Latin synopsis as well as his drawings of the 

 receptaculum seminis and abdomen that this species is synonymous 

 with C. varicans Sars. His drawing of the receptaculum seminis 

 shows this organ to have the form of that pictured by Schmeil (Taf. 

 VI, fig. 3) with a slightly greater expansion of the "wings" of the 

 anterior division. By a careful study of this organ in a number of 

 specimens, I have concluded that what Lilljeborg pictures as the 

 receptaculum seminis of the type C. varicans (see Taf. IV, fig. 24, of 

 his paper of '01) is the extreme form of narrow anterior portion, 

 Schmeil's drawing showing a slightly greater expansion of this same 

 division. Lilljel;)org's drawing of the receptaculum of C. rubellus and 

 my own (PI. Ill, fig. 10) of this organ in C. varicans are examples of 

 the extremely wide and wing-like form. The proportional lengths 

 of the caudal setse, as shown by Lilljeborg, are identical with those 

 of the typical varicans (PI. Ill, figs. 6 and 7). 



Miss Byrnes in her recent paper (March, '09) has described a species 

 of Cyclops under the name of C. bicolor. Her description of the 

 antenna, which she states "contain each twelve segments," at once 

 suggests C. varicans, for nowhere do I find a record of C. bicolor with 

 more than eleven joints in the first female antenniB. Schmeil gives 

 eleven, Lilljeborg 10-11, and Marsh has noted a form with ten 

 segmented antennae, though he finds the usual number is eleven. 

 Herrick, with whose description she seems to have compared her 

 own, also gives eleven as the number of female antennal segments. 

 Miss Byrnes' formula for the swimming feet agrees exactly with that 

 of specimens examined from this locality. In speaking of the 

 variation of this species, she says: "The species C. bicolor is usually 

 placed {e.g., by Marsh) among Cyclops having ten or eleven segments. 

 The occurrence, therefore, of a twelve-jointed antenna shows that 

 considerable variation may occur in this organ. Except in this 



