ENTOMOSTRACA OF MINNESOTA. 117 



Cjclops gracilis Lilljebogg. 

 Plate XIX, Figs. 10, 11. 

 Lilljeborg '53; Schmeil '91 (diaphanus), aod '92. 



Apparently this is a distinct species, characterized by the slender 

 form, especially of the abdomen, which is to the thorax as 5:7, di- 

 vergent cylindrical stylets, short setse and form of the fifth foot and 

 receptaculum. The antenute are slender, reaching the caudal border 

 of the fourth segment, and are of the form of the 12 jointed species; 



formula -■ -^^- rrr. Fifth foot with a broad basal segment 



and a cylindrical terminal one, which bears a short spine and a long 

 seta. Eggs few. Feet all two jointed. Schmeil speaks of the fifth 

 foot as one-jointed, but the fact that the basal segment is immovably 

 soldered to the body should not prevent us from recognizing its 

 existence. This species has been found only in Sweden, Poland and 

 Germany. 



Cyclop.s (liapliaims Fischer. 



Plate XIX, Figs. 6-9. 



Fischer '53; Claus '63 (minutus); Heller '63 (minutus'); Daday '85^ (frivaldszkyi) ; 

 Sostaric '88; Schmeil '92. 



The above syuonomy is derived from Schmeil's monograph, which 

 can hardly be considered very authoritative since its author never 

 saw the species and offers only comparative data to discriminate this 

 species from the last. Abdomen broader than (7. hicolor, stylets as 

 long as the two preceding segments, lateral seta nearer the base than 

 the end. The lateral apical setfc short, equal, median setic as 2 : 3. 

 Antennae 11-jointed, short, only reaching the second segment. Swim- 

 ming feet with two-jointed rami. Fifth foot with a short spine and 

 long seta at the end of the cylindrical apical joint. 



* Cyclops affiuis Sars 



Plate XXX, Figs. 9-11. 



Sars '63; Uljanin '75; Brady '78; Rehberg '80 (pygmreus); Daday '85' (pygmaeus, 

 and affinis); Herrick '84; Vosseler '86; Lande '90; Kichard '91; Brady '91; 

 Schmeil '91 aud '92. 



Schmeil makes the statement that "Herrick regards C. affinis as 

 ' var, b.' of C. plmleraius Koch, and identifies it with his C. adolescens,^^ 

 overlooking the plain statement that "it is impossible to sufficiently 

 identify it [the American form] with any of the above," and the fact 

 that Sars' description was appended in a separate rubric. Schmeil 

 devotes considerable time to the relations of C. adolescens and is nob 

 unnaturally provoked by the inconsistencies in the two references, 

 which are explained, however, by two provoking typographical errors 



