PYCNOGONIDS 277 



Remarks. The 3-jointed chelifori, the g-jointed palpi, and the absence 

 of a marked protuberance on the dorsodistal extremity of the femoral 

 joint clearly relate this form to A. tuberculata, and to those forms which 

 I have placed with it in the genus Ammothella, viz., three species from 

 the Gulf of Naples (see ' Remarks,' p. 273). 



The two mature specimens of this lot were both females with ova in 

 various stages of development in the second and third coxal and femoral 

 joints of the legs. 



The species is well characterized by the long eye tubercle and the 

 longer, spiny, elevated, and curved caudal segment, the spines on the 

 dorsal surface of the body, and the long, slender spines of the legs. 



Genus Tanystylum Miers ('79). 



Trunk broad; lateral processes comparatively short and closely 

 crowded, making the body disciform ; segmentation suppressed. Cheli- 

 fori usually mere i -jointed knobs; sometimes 2-jointed; chelate in 

 immature specimens. Palpi with 6 or 7 joints ; first and third joints 

 short, second and fourth longer. Femoral joint of legs of female con- 

 siderably swollen. Openings of oviducts in usual position on all four 

 legs. Openings of the genital ducts of the male not upon genital pro- 

 tuberances. 



Remarks. The genus Tanystylum is undoubtedly very closely related 

 to Ammothea, but differs in several important respects. I was at first 

 inclined to include Clotcnia with this genus, as Schimkewitsch has done 

 (Schimkewitsch, '89), but in view of the highly concentrated body, 1 

 closely approximated eye tubercle and caudal segment, 4-jointed 

 palpi, and male genital openings in the second as well as the third and 

 fourth pairs of legs, I think it may well be left, for the present at least, 

 as a separate genus. 



The species which I have here called Tanystylum intermedium differs 

 from previously described species of the genus in having 2-jointed che- 

 lifori, and from all but T. chierchia Schimkewitsch ('89, p. 333) in 

 having 7-jointed palpi instead of 6-jointed. It is, however, so similar 

 in other respects that a separation into another genus does not seem 

 justifiable. 



Discoarachne brevipes Hoek ('8ia, p. 74) is undoubtedly very closely 

 related to the forms under discussion, and perhaps should be classed as a 

 species of Tanystylum. 



^Dohrn ('81, p. 162) well says: "Dieses Thier \_Clotenia conirostris] hat die bei 

 weitem concentrirteste Gestalt aller Pantopoden, die ich kenne." 



