138 PROCEEDINGS OF THE NATIONAL MUSEUM vol. los 



Through a study of literature and comparison of descriptions with 

 the Tortugas material, it is apparent that Lampoidojms marki Esterly 

 from Bermuda and Suezia canalis Gurney from the Suez Canal are 

 very closely allied to Ridgewayia typica. Of these species, only 

 marki is known from both sexes, and has been listed in literature 

 beyond the original record. Only the female of typica has been 

 described; canalis is known only from the male. A single male speci- 

 men, representing either an unknown species or the male of typica, has 

 been briefly described from Madras as Suezia sp. by Krishnaswamy 

 (1953). Both this Madras male and that of canalis are relatable to 

 the female of Ridgewayia typica through knowledge of both sexes of 

 marki and the new Tortugas species. On the basis of present knowl- 

 edge, there seems little justification for maintaining three generic 

 names for this small group of species, and they are all herein referred 

 to Ridgewayia (R. typica, R. marki, and R. canalis) . 



Specimens of only the new species have been available for study. 

 The specific diagnoses included here are all based upon the original 

 descriptions (text and figures) ; note is made of characters omitted in 

 these descriptions. 



Generic synonymy 



The results of study of the literature and of the available specimens 

 do not permit an absolute, unqualified synonymy of the generic names 

 that have been proposed. Therefore this study is presented with the 

 recognition and suggestion that Lampoidopus and Suezia may with 

 increased knowledge be fully and satisfactorily separable generically 

 from Ridgewayia. That this is not now possible is due largely to the 

 fact that in Ridgevjayia and Suezia only the one sex is known. If I 

 were presenting a paper dealing only with literature, or with speci- 

 mens of the same sexes as were originally available for the described 

 species, it would seem sufficient to point out the hitherto unsuspected 

 relationship of Ridgewayia typica, Lampoidopus marki and Suezia 

 canalis. Since, however, there exists the primary problem of placing 

 two new species as accurately as possible, it has been necessary to 

 consider critically the question of whether there is any valid objective 

 reason for not placing them in the genus of prior date. 



The generic diagnosis given for Ridgewayia by Thompson and Scott 

 (1903) confused the exopod and endopod of the antenna, and gave no 

 information for the third leg of typica. It is also possible that the 

 presence of an inner seta on the first basipod segments of legs 1 and 2 

 may have been overlooked. It is doubtfid if the setation shown in 

 the figure of the antennule is entirely exact. Otherwise the descrip- 

 tion is complete and accompanied by excellent figures. It affords 

 therefore an adequate basis of support for inclusion in the genus 

 Ridgewayia of the females of the new Tortugas species and of Esterly's 



