FREE-SWIMMING COPEPODS OF THE WOODS HOLE REGION. 
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maxilliped reaching clown about to distal edge of second basal). Right fifth foot has outer ramus 
without an internal bristle; terminal bristle thorn-shaped, sometimes denticulate; left fifth foot has 
inner ramus, as on right side; basal and first and second joints of outer ramus elongated, so that right 
outer ramus (exclusive of terminal bristle) reaches at least to middle, at most as tar as end of second 
joint of left outer ramus; third joint of outer ramus abbreviated. 
Coloration: Rather transparent, with rather irregularly distributed red pigment in body and 
sometimes in appendages. In some individuals color is lacking except in anal region. Eggs yellowish 
or reddish. 
Length of female, 2.7 to 4.5 mm ; of male, 2.35 to 3.2 mm. 
Numerous colorless female specimens of this thoroughly pelagic, widespread, and economically 
very important species were taken in the tow by the Fish Hawlc in Vineyard Sound, near Gay Head, 
1 . Calanus finmarcMcus Gunner: a, female, dorsal 
aspect; 6, basal portion of fifth pair of legs. 
2. Calanus minor Ulaus; a, female, dor- 
sal aspect; b, female, fifth foot. 
Marthas Vineyard, July 10. My specimens do not show a marked concavity of inner border of basal 
joints of fifth pair of legs, but in other respects they conform with Giesbreclit’s description. 
2. Calanus minor Claus. 
Female: Head and first thoracic segment united ; front and lateral portions of fifth thoracic segment 
rounded; furcal bristles symmetrical, the longest twice as long as abdomen and twice as thick as 
other bristles. Anterior antennae not reaching to posterior end of trunk; festhetasks not duplicated 
on any joints. Distal margin of second basal joint of second to fourth pairs with pointed projection; 
ratios of lengths of pieces of third joint of outer ramus as 5 : 4; 10:7 ; 2 : 1. First basal joint of fifth pair 
of feet along inner border with straight margin, less finely denticulated than in C. finmarcMcus. 
Male: Head and first thoracic segment fused. Anterior antenna: curved (joints 1 and 2, 3 to 5, 24 
and 25 fused). Mouth parts similar to those of female (outer bristle of fourth joint of inner ramus of 
posterior maxillipeds extending down nearly to distal edge of second basal). Right fifth foot has third 
joint of outer ramus with only 2 inner bristles and a short, thorn-shaped terminal bristle; left fifth 
foot with only 3 small bristles ou third joiut of inner ramus. 
Length of female, 1.8 to 2 mm.; of male, 1.7 to 1.8 mm. 
Numerous female specimens taken in Gulf Stream tow, July 25, 1899. This species has a very 
wide range of distribution. 
