618 PROCEEDINGS OF THE NATIONAL MUSEUM. tol. 47. 



and because the accounts of the American species are widely scat- 

 tered, and in some instances difficult of access, it has been thought 

 best to include here all that is known of them, together with some 

 new figm"es which admit of easy comparison. 



Synonyms. — Achtheres carpenteri Packard, 1874, p. 612, fig. 1, 

 text, according to the characters here established can not belong to 

 this genus at all, and is accordingly transferred to the new genus 

 Salmincola (see p. 616). 



Achtheres selachiorum Kurz, 1877, p. 385, pi. 25, fig. 1; pi. 27, figs. 

 38 to 40, is the only species found in salt water, and was stated by 

 Claus to be the undeveloped young of Lernaeopoda galei. 



Toward the close of his description of this "new species" Kurz 

 stated that Lernaeopoda galei had been found upon the same host and 

 in the same place. But, he added, "The identity of the two species 

 does not appear possible. The great differences in form in L. galei, 

 as van Beneden himself shows, may possibly be an indication of a 

 difference in species (p. 388). That which induces me to cling to this 

 new species is the elongate body form, the longer and narrower egg 

 sacks, the club-shaped anal laminae, the distmct segmentation of 

 the body, and the three-parted form of the attachment button in 

 L. galei, not to mention other minor differences in the structure of 

 the mouth parts" (p. 389). 



All the differences enumerated by Kurz admit of easy explanation 

 provided the specimens he secured were undeveloped young of 

 L. galei, and this would be further indicated by the size he has given 

 for them. On the other hand, to try and make of them a new species 

 of Achtheres is impossible, because they are so large for that genus that 

 they must be mature adults, but they possess a pair of good-sized 

 posterior processes, they have no abdomen comparable with that in 

 Achtheres, while the first maxillae are tripartite and have a palp. 

 We are hence forced to accept Claus's statement that this species is a 

 synonym of L. galei. The "Achtheres sp." mentioned by Wright 

 (1892, p. 438, fig. 10, text) is probably the same as Kr0yer's A. pime- 

 lodi (see p. 628). 



TABLE OP SPECIES. 



1. Cephalothorax about as wide and as long as the trunk; bulla an enormous disk (3 

 mm. in diameter); maxillipeds reaching the frontal margin of head. 



corpulentus Kellicott, 1880, p. 619. 



1. Trunk once and a half to twice the length and width of the cephalothorax; bulla 



and maxillipeds normal size 2. 



2. Abdomen much narrower than, and joined abruptly to, the trunk, inclined ante- 



riorly and more or less distinctly segmented 3. 



2. Abdomen the same width as the posterior portion of the trunk and passing imper- 



ceptibly into it; in the same line as the trunk axis, and with no traces of seg- 

 mentation 4. 



3. Arms stout; carapace much widened anteriorly; second antennae almost touch- 



ing across the frontal margin; first antennae distinctly jointed. 



micropteri Wright, 1882, p. 620. 



