604 PROCEEDIXGS OF THE NATIOXAL MU8EVM. tol. 17. 



Type. — Salmincola sdlmonea (Lernaea salmonea Gissler). 



(Salmincola, Salmo, the host family and incola, a dweller.) 



Remarlcs. — This new genus differs from Lernaeopoda in the absence 

 of a dorsal carapace on the cephalothorax, in the fact that the first 

 thorax segments are not differentiated, in the absence of posterior 

 processes and a palp on the first maxillae, and in the presence of a 

 genital process. From Lernaeopodina it may be distinguished by the 

 absence of a dorsal carapace, posterior processes, and the palp on the 

 first maxillae, by the presence of a genital process, and by the structure 

 of the maxilhpeds. 



From AcMheres it may be separated by the configuration of the 

 top of the head (see figs. 19 and 69), by the absence of a neck and 

 abdomen, by the presence of a genital process, and by the form of the 

 second anteimae, which are folded across the front of the head in 

 AcMheres, but are carried straight forward in Salmincola. 



The only male of the genus thus far discovered is that of edwardsii 

 which has recently been described and figured by Fasten.^ 



It shows a much closer relationship to AcJitlieres than to Lernae- 

 opoda, but may be distinguished by its smaller size, by the curvature 

 of the cephalothorax and trunk, and by the structure of the second 

 antennae. 



TABLE OF SPECIES. 



1. Body two or three times as long as the cephalothorax and much wider, flattened 

 dorso-ventrally and not inflated 2. 



1. Body and cephalothorax of about the same length, trunk mder and considerably 



inflated, sometimes spherical; arms much shorter than the trunk and with a 

 petioled bulla 7. 



2. Cephalothorax as wide or wider than long and nearly in line with the trunk 3. 



2. Cephalothorax much longer than wide and at right angles to the trunk axis 6. 



3. Arms straight and considerably longer than the trunk 4. 



3. Arms more or less cvu-ved and shorter than the trunk 5. 



4. Bulla funnel-shaped; two chitinous appendages between the bases of the first 



maxillae alpina (Olsson), 1877. 



4. Bulla mushroom-shaped; body much flattened, thinner posteriorly than anter- 

 iorly californieiisis (Dana), 1852, p. 605. 



4. Bulla orbicular with a long petiole; maxiUipeds large and stout, without accessory 



spines carpionis (Kr0yer), 1837, p. 606. 



5. Bulla scoop-shaped, with its concave ventral surface applied to the outside of the 



gill filament; maxillipeds with accessory peg on ventral surface of basal 

 joint salmonea (Gissler), 1751, p. 607. 



5. Bulla pear-shaped ; maxillipeds with a minute tooth on the inner margin of terminal 



joint coregonorum (Kessler), 1868. 



6. Bulla mushroom-shaped and petioled, arms longer than the trimk; maxillipeds 



plainly visible, with a large papilla on the basal joint 



siscowet (Smith), 1874, p. 608. 



6. Bulla mushroom-shaped and petioled; arms longer than the trunk and covered 



with a "vagina;" maxillipeds concealed between the arms and without 



papillae lotae (Olsson), 1877. 



1 Biol. BuU., vol. 27, p. 116, pis. 1-3. 



