710 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xixiii. 



and close to the point of the rostrum. The antennula (Plate LXI, fig. 

 3) is claviforni Avith the anterior border set with short spines through- 

 out its length. The sensory seta is near the proximal end. The 

 distal end of the antennula is obliquely truncate, slightly spinose, 

 especially on the posterior angle, and with about nine lanceolate 

 processes of varying lengths. The antennae (Plate LXI, fig. 4) have 

 the margins of the joints spinose. From the basal joint of the three- 

 jointed ramus is a long process, longer than any of the others and 

 much stouter. The outer joint of this is armed with short, stout 

 spines. 



A few specimens of this species were found in the material from 

 Great Caribou Island, opposite Battle Harbor, Labrador, July 14, 

 1906. This species is widely distributed in Europe and North 

 America. 



Family LYNCEID^. 



Genus EURYCERCUS Baird, 1843. 

 EURYCERUS GLACIALIS Lilljeborg. 

 Plate LXI, fig. 5 ; Plate LXII, figs. 1-3. 



Eurycercus glaciaUs Lilljeborg, Contributions to the Natural History of the 

 Commander Islands, On the Entomostraca collected by Mr. Leonhard 

 Stejneger, on Bering Island, 1882-83, Proc. U. S. Nat. Mus., X, 1887, 

 p. 154; Cladocera Suecife, Nova Acta Reg. Soc. So. Upsala, 3d ser., 

 XIX, 1900, p. 393, pi. Lx, fig. 11, pi. LXI, figs. 1-13. 



Length of females about 4.5 mm. 



This is the largest species in the collections and one of the largest 

 of the Cladocera. The outline and general appearance is shown in 

 Plate LXII, fig. 1. The pigment fleck is small and placed some dis- 

 tance back from the rostrum. The ornamentation of the shell is made 

 up of a network of irregular polygonal meshes (Plate LXII, fig. 3). 

 The antennula (Plate LXI, fig. 5) is broadest near the basal portion 

 and then gradually tapers toward the outer end. It is marked by rows 

 of fine setee arranged in three rows as seen from one side. The distal 

 end has a number of short spinose projections, and at the end of the 

 antennula are inserted a number of elongated projections. The 

 sense seta is close to the distal end of the antennula, thus differing 

 from E. lamellatus {O. F. Midler), wdiich has it at about the middle 

 and broadest part. The post-abdomen (Plate LXII, fig. 2) is large 

 and bordered by a row of closely set teeth. The borders of this part of 

 the animal are much thicker and darker in color than in the common 

 species E. lamellatus (O. F. Miiller). 



A number of specimens of this species were found by Doctor Allen 

 at Battle Harbor, Labrador, on July 14 and August 1, 1906, and on 

 Great Caribou Island July 14, 190G. 



