REPORT ON THE AMPHIPODA. 1609 



uropods, about equal in length to the fourth and coalesced fifth and sixth segments of 

 the pleon together, the apex acute. 



Length, in a bent position, two inches and a tenth, fully outstretched about two inches 

 and a half. 



Locality. — Station 347, April 7, 187G ; Equatorial Atlantic; lat. 0° 15' S., long. 

 14° 25' W. ; surface net; surface temperature, 82°. One specimen. 



Remarks. — The synonymy of this species is given under reserve, since there was 

 only a single specimen for examination, while other writers have been able to compare 

 several examples. The type described by Milne-Edwards was evidently a male; its 

 length is said to be about an inch, with the head as long as all the rest of the body, 

 and the telson, "un stylet impair," as long as the body. The expressions are vague, 

 since "all the rest of the body" may or may not include the "stylet impair," which is 

 itself said to be as long as the body, the body in this instance probably meaning the 

 perseon and pleon together. Spence Bate describes a female specimen under the name 

 " Rhabdosoma armatum," and a male under the name " Rhabdosoma Whitei." Claus 

 both in 1879 and 1887 declares that these are the two sexes of one species. Streets in 

 1878, under the name "Rhabdosoma whitei, Bate," describes a male, and figures 

 a female, and further describes and figures, under the name " Rhabdosoma armatum 

 (Edw.), Adams and White," a young male, taken at the same place with six out of his 

 seven specimens of ''Rhabdosoma whitei." In the synonymy he states that " Rhabdo- 

 soma armatum, Adams and White, Voyage of the ' Samarang,' 1850 [1848], Zoology, 

 Crust., p. 63, pi. 13, fig. 7," is not " R. armatum, Bate, Catalog. Amphi. Crust., 

 1862, p. 344, pi. 54, fig. 6," though he recognises that White and Spence Bate are 

 apparently describing the same specimen. 1 Bovallius in 1837 distinguishes " Rhabdo- 

 nectes armatus" from " Rhabdonectes Whitei," but whether from his own observation 

 or relying only on published accounts he does not indicate. Dr. Giles gives a beautiful 

 figure of a male specimen, under the name Rhabdosoma investigatoris, the measure- 

 ments of which agree very fairly with those given by Claus for one of his male 

 specimens. In the perseopods of Dr. Giles' specimen the second joint is shown with a 

 very acute apex, and it is so figured by v. Willemoes Suhm in the first three pairs 

 of perreopods, but neither Dr. Giles nor any other author describes this feature, nor 

 could I detect it in the specimen above described. The more obvious and exceedingly 

 striking peculiarities of this genus have so much absorbed attention, that comparatively 

 little has been paid to minuter details. A tooth on the hind margin of the wrist 

 of the first gnathopods is figured both by Claus and Spence Bate for the female 

 of "Rhabdosoma armatum"; Spence Bate gives no such tooth in his figure of 

 the first gnathopods of Rhabdosoma ivhitei (curvicorne); Streets does not give it 



1 The specimen had clearly suffered some damage before it came into Spence Bate's hands, hut even so the pleon 

 in his figure of it cannot easily be reconciled with that in White's. 



(ZOOL. CHAIX. EXP. PART LXVII. — 1888.) Xxx 202 



