532 PYCNOGON1DA 



about four rows of teeth ; five pairs of legs, destitute of accessory 

 claws ; genital apertures on all the legs (Bouvier). 



Decolopoda australis, Eights 1 (1834), a remarkable form from 

 the South Shetlands, recently re-discovered by the Scotia expedi- 

 tion. The animal is large, seven inches or more in total span, 

 in colour scarlet ; it was found in abundance in shallow water 

 and cast upon the shore. The body is greatly condensed, the 

 proboscis is " clavate, arcuated downwards," and beset with 

 small spines. A second Antarctic species, D. antarctica, has been 

 described by Bouvier. The presence of a fifth pair of legs 

 distinguishes Decolopodci from all known Pycnogons, except 

 Pentanymphon. Stebbing would ally Decolopoda with, or even 

 include it in, the Xymphonidae ; but the presence of a second 

 joint in the chelophoral scape, the number of joints in, and the 

 armature on, the ovigerous legs, and the deflexed proboscis, are 

 all characters either agreeing with or tending towards those of 

 the Eurycididae ; while the Colossendeidae would be very like 

 Decolopoda were it not for the complete suppression of the 

 chelophores. It seems convenient to constitute a new family 

 for this remarkable form. 



Fam. 2. Colossendeidae (Pasithoidae, Sars). Appendage I. 

 absent in adult ; appendage II. very long, 10-jointed; appendage 

 III. 10-jointed, clawed, with many rows of teeth ; auxiliary claws 

 absent ; segments of trunk fused ; proboscis very large, somewhat 

 mobile ; genital apertures, in at least some cases, on all the legs. 



Pasitlioe, Goodsir (1842), which Sars assumes as the type of the 

 family, is here relegated to Ammotkea. 2 Colossendeis, Jarszynsky 

 (1870) (Anomorhynchus, Miers (1881), Rhopalorliyiiclms, Wood- 

 Mason (1873)), remains as the only genus commonly accepted : 

 large, more or less slender _ short -necked forms ; world -wide, 

 principally Arctic, Antarctic, and deep-sea ; about twenty-five 

 species. 3 The largest species, C. gigas, Hoek, from great depths 



Exped. 1899 ; Mobius, Fauna Arctica, 1901, Valdivia Exped. 1902 ; Cole, ffarri- 

 'inan Alaska Exped. 1904 ; Hodgson, Discovery Exped. 1907 ; Bouvier, Exp. 

 Antarct. Fr. 1907. 



1 Boston Journ. Nat. Hist, i., 1834, p. 203 ; Cf. Hodgson, Pr. E. Phys. Sac. 

 Edinburgh, xvi., 1905, p. 35 ; Zool. Anz. xxv., 1905, p. 254 ; Discovery Exp., 

 "Pycnogonida," 1907 ; Bouvier, Exp. Antarct. Fr. 1907. 



2 See pp. 535, 541. Cf. Dohrn (t. cit.), p. 228. 



3 The first known species was described as Phoxichilus proboscideus, Sabine, 

 from the shores of the North Georgian Islands (1821). 



