PYCNOGONIDA OF NEW ENGLAND AND ADJACENT WATERS. 485 



Color of alcoholic specimens, ligbt yellowish brown. Length 1.4 

 millimeters; extent 5.2 millimeters. 



Three specimens only, taken in the Bay of Fundy by the United 

 States Fish Commission, in 1872. In general appearance it is closely 

 similar to Achelia spinosa. It is apparently nearest to the ^'Amniothoa 

 hrevijpes,''^ of Hodge, described from the Durham coast, though quite 

 distinct from that species, so far as can be judged from the original 

 figures. The antennoe, in our species, are more slender and with much 

 smaller spines on the chela, and the proportions of the palpal joints are 

 very different ; the abdomen is far longer and more slender, and the 

 legs are not so spinous. 



Sjiecimens examined. 



Nymphon Chr. Fabricius. 



Body slender. Neck distinct. Eostrum cylindrical, rounded. An- 

 tennse three-jointed, chelate. Palpi five-jointed. Accessory legs present 

 in both sexes, eleven-jointed. Legs slender ; dactylus with auxiliary 

 claws. 



All the species of Nymplion are slender, some of them exceedingly so. 

 The antennae are slender and the claws of the chelae are armed along their 

 opposable edges with a series of close-set, slender spines. The sexes 

 generally resemble each other closely, the chief differences being found 

 in the accessory legs. These appendages are armed, in both sexes, with 

 a series of flattened denticulated spines, found upon the seventh, eighth, 

 ninth, and tenth joints. The auxiliary claws are usually of small size, 

 and sometimes minute. They are XDCCuliarly deep-water forms, rarely 

 occurring at a depth of less than twenty fathoms, and sometimes extend- 

 ing down to great depths. For this reason almost nothing is known of 

 their habits, though their external development has been well studied. 

 In certain species the specific characters are extremely variable, as de- 

 scribed below. 



Nymphon Stiomii Kroyer. 



Nat. Tidss.*, IsteBind, 2det Hsefte, p. Ill, 1844; Voy. en Scand., Laponie, etc., 

 pi. 35, figs. 3 Or-f. — Norman, Eept. of the Brit. Assoc, for the Advancement 

 of Sci. for 1868, p. 301.— Miers, Ann. and Mag. Nat. Hist., 4th series, vol. 20, 

 No. 116, p. 109.— Wilson, Trans. Conn. Acad., vol. v, p. 17, PI. VI, figs, la to 

 1?!., July, 1878. 



Probably Pycnogonum grossipes Abilgaard, in O. F. Miiller's Zoologica Danica, 

 vol. iii, p. 67, PL CXIX, figs. 5-9, 1788. 



