No. 26.] ARTHROSTRACA OF CONNECTICUT. 229 



1880. Erichsonia filiformis, Harger, ibid., for 1878, p. 355, 

 pi. 7, figs. 38-41. 



1905. Erichsonella filiformis, Richardson, Bull. U. S. Nat. 

 Mus., No. 54, p. 401. 



Fig 73- Erichsonella filiformis. 



Body oblong-ovate, about three and one-half times as long as 

 wide; abdomen as long as greatest width of body. Head with 

 front margin deeply excavate between the prominent antero- 

 lateral angles ; dorsal surface of head with a prominent, rounded 

 elevation bearing two slender, rounded tubercles, one on each 

 side of the middle line. Eyes large, round, compound, situated 

 at about the middle of the head at the extreme lateral margins. 



First antennae with basal joint large and dilated; second and 

 third joints subequal and only slightly shorter than first; fourth 

 joint a little longer than third; extending to end of third joint 

 of second antennae. Second antennae with first joint very short; 

 second and third joints subequal in length and equal to the first 

 two joints of the first antennas combined; fourth joint nearly 

 twice as long as third ; and fifth shorter than fourth ; flagellum 

 clavate, as long as fourth joint, extending when retracted about 

 -as far as hind margin of fifth thoracic segment. 



