MARINE AMPHIPODA IN MICRONESIA — BARNARD 509 



coxa of AI. mastersi (this statement appears on p. 48 under M. othonop- 

 sis, new species). Chilton had written in his remarks that the first 

 coxa was like that of M. bruzelii Stebbing (1888), which, if closely 

 examined, appears to have the coxa acutely produced forward. 

 Stebbing's (1906) description of AI. mastersi was undoubtedly based 

 on the poor original figm-es of Haswell (1879b). Although Sheard 

 (1936) mentioned variability, his redescription of M. mastersi seems 

 to fit most of Chilton's (1916) remarks except for the heavier palmar 

 teeth of gnathopod 2. At this stage of the situation one must accept 

 Sheard's figuring of the species as a startmg point. In so doing, 

 one is immediately struck with the similarity of that description 

 with the redescription of Alaera othonides Walker by Pirlot (1936), 

 who relegated it to a new genus Linguimaera, since rejected. I am 

 unable to see any qualitative differences between the two redescrip- 

 tions. Walker (1904) originally figured only the uropods, telson, and 

 third pleonal epimeron. Only in the telson can one find a discrepancy: 

 Sheard described a telson with narrow lobes, evenly notched; Walker 

 described narrow lobes quite asymmetrically notched. Chiltoji's 

 (1916) description would seem to fit Wallver's better than Sheard's, 

 so we are left with the possibility that the telson varies to such ex- 

 tremes. 



K. H. Barnard (1916) described but did not figure a specimen of 

 Adaera mastersi from South Africa in which one male gnathopod had 

 rather strong and acute palmar teeth, especially having a distinct 

 defining tooth; the other gnathopod was smaller, with the palm 

 ill defined and lacking teeth. K. H. Barnard also described South 

 African Alaera hamigera with figures of two kinds of gnathopods, one 

 of which is similar to the aberrant form herein described. The other 

 gnathopod is in a somewhat intermediate condition between right and 

 left gnathopods of adult males as herein described. I am not certain 

 how he distinguished these specimens from his AI. mastersi, since this 

 intermediate second gnathopod fits his description of the M. mastersi 

 gnathopod to a degree. 



The variability seen in the present material makes necessary the 

 suggestion that Alaera mastersi and M. othonides, which themselves 

 are most certainly closely related if not synonymous, may be growth 

 stages of M. hamigera. This is vaguely contradicted by the fact that 

 Ad. mastersi has been reported so many times previously but no worker 

 has related it to M. hamigera. One may inspect Sheard's and Pirlot's 

 drawings and still see minute differences in the gnathopodal palms 

 between M. mastersi and M. hamigera and the writer leaves this as 

 the only way to separate the species at present. In J. L. Barnard's 

 (1962b) key to Maera, the species have been separated by considering 

 only developed adult males, assuming that Ad. mastersi is such. 



