﻿PYCNOGONIDA. 



34 



essential reason for me to incorporate the two families has been the fact that Pallenopsis which is 

 most closely related to the genus Pallcne, shows, by the formation of its palps that it will not do to 

 lav too much stress upon the presence or absence of these organs. 



I. Subfam. Nymphonini. 



Palpi expleti, pluries partiti. 



Palps well developed, with more joints. 



I. Gen. Nymphon (Fabr. 1794). 

 Nymphon, Wilson, Syn. Pycnog. New-Engl., 1878. 

 Chaetonymphon, Sars, Pygnog. bor. arct, 1888, pro parte. 

 Boreonymphon, Sars, ibid. 

 The genus XyiiipIio)i with the limits which Iiave been given to it here by Wilson, includes 

 a great number of species that might naturall\- be distributed to several groups, but the differences 

 seem to me to be too small to justif}' the division into more genera, or the separating of more or 

 fewer species of the genus XyiiipJioii of Wilson. The genera Cluetonyinphon and Boreonymphon^ 

 for insL, which have been separated by Sars, I.e. p. 352 and 354, seem to me too little characteristic 

 to be taken as more than groups of species, and with regard to ^V. macronyx which has been referred 

 to Chccfonyiiiphon, I think it even doubtful, if it might not more easily be placed among the species 

 that Sars still keeps as the genus Nymphon. 



The species of the genus, brought home by the Ingolf, may be arranged as shown in the 

 following analytical table. 

 a. The trunk naked. 



(The fingers of the chehe (i. e. both the immovable and the movable finger) dentate. 

 The auxiliary claws well developed), 

 b. The oculiferous tubercle pointed. 



b. b. The oculiferous tubercle truncate. 



c. The first tarsal joint shorter than the second. 



c. c. The first tarsal joint as long, or longer than the second, 

 d. The two last joints of the palps short and thick. 

 (The claws short, powerful. 

 The fingers of the chelse short). 



1. X. grossipes P'abr. 



2. N. Sluiteri Hoek. 



3. X. brevitarse Kr. 



d. d. The two last joints of the palps long, thin, 

 e. The claws short, powerful. 



4. X. serratum G. O. Sars. 



5. X. megalops G. O. Sars. 



6. X. Sarsii n. sp. 



7. X. Hoekii n. sp. 



8. X. Stroemii Kr. 



