I. '08. 72 



Size. — The type specimen measures 56 mm. (Smith), while 

 the example taken by the Challenger expedition is 57 mm. 

 in length. 



General distribution. — Two specimens only are known. 

 One was found off the east coast of the United States, lat. 

 40° 26' 40" N., long. 67° 5' 15" W. (Smith), while the other 

 was taken in the Pacific, lat. 26° 29' N., long. 137° 57' E. 

 (Spence Bate). 



Irish distribution. — 

 Helga. 

 S,R. 449—19 /5 /'07.— 50° 28' N., 11' 39' W. Soundings 950 fathoms. 

 Midwater trawl, 0-700 fathoms. — One, 24 mm. 



Vertical range. — Trawled in 949 fathoms (Smith) and 2,425 

 fathoms (Spence Bate) ; probably a midwater species. 



Genus Hymenodora, G. 0. Sars. 

 Hymenodora, Spence Bate, 1888 (partim).'^ 



Hymenodora glacialis (Buchholz). 



PI. VIII, figs. 1-3. 



Hymenodora glacialis, G. O. Sars, 1885, PL iv. 

 Hymenodora glacialis, Smith, 1886, PI. xv, figs. 3 and 10 ; 



PI. XVI, fig. 5. 

 Hymenodora gracilis. Smith, 1886, PI. xii, fig. 6. 

 Hymenodora glacialis, Faxon, 1895. 



The carapace is hardly at all compressed ; it is dorsally cari- 

 nate in the anterior half and is produced to a short, acutely 

 pointed rostrum wdiich reaches about as far forward as the 

 eyes. The anterior part of the carapace and rostrum form a 

 sort of hood which projects over a portion of the ocular region. 

 Dorsally the rostrum is provided with from four to six small 

 forwardly directed teeth. Prom the orbital sinus a well- 

 marked groove runs backwards and downwards and another, 

 less pronounced, defines the superior boundary of the bran- 

 chial region. 



The abdominal somites are all evenly rounded above ; the 

 sixth is rather less than twice the length of the fifth. The 

 telson reaches considerably beyond the outer uropods ; it is 

 dorsally sulcate and is narrowest in its distal third, becoming 

 broader again terminally. The apex is rounded and is fur- 

 nished with from four to seven spines, of which the outermost 

 are much the longest ; dorso-laterally it is provided with a few 

 pairs of minute spinules. 



1 In a previous paper (1906, (1), p. 19) I have shown that two of the 

 species which appear in the ChaUenger Report under this genus, must 

 be transferred to Acanthephyra. 



