5 1 2 PYCNOGONIDA CHAP. 



themselves to one another and to the ovigerous legs of the male 

 parent. In Nymphon hamatum, Hoek, the several filaments 

 secreted by the separate sacculi of the gland issue separately. 

 In Pycnogonum the spine on which the gland opens is itself 

 prolonged into a long fine filament, and here, according to 

 Hoek, the gland is in all probability functionless and rudi- 

 mentary. Hoek has failed to find the gland in Ascorhynchus, 

 and also in certain Nymphonidae (e.g. Boreonymplion robustum, 

 Bell), in which the young are more than usually advanced at 

 the time of hatching. The gland has also been described by 

 Lendenfeld and others in Phoxicliilidium, whose larvae do not 

 cling together but live a parasitic life ; in this genus the long 

 spine or tubercle is absent on which the orifice is usually 

 situated, and, according to Lendenfeld, the secretion issues 

 from many small orifices set along the opposing edges of the 

 chela. Of the two species described by Dohrn as Barana castelli 

 and B. arenicola, the former has the spine of inordinate length, 

 more than twice as long as the whole body, chelophore and all ; 

 while in the latter (which species rather resembles Ascorhynchus} 

 the spine is altogether absent. 



In the palps and ovigerous legs of the adult are found 

 glandular bodies of a hollow vesicular form with a simple lining 

 of cells, the vesicle being divided within by a septum with a 

 central orifice, the outer and smaller half opening to the exterior. 

 These glands are probably of general occurrence, but they have 

 been but little investigated. They lie usually in the fourth and 

 fifth joints of the palp, and the third and fourth joints of the 

 ovigerous leg. Hoek describes them in Discoarachne (Tanystyluni) 

 as lying within the elongated third joint of the palp, and opening 

 by a sieve-plate at the end of the second joint. In Ammotliea 

 (Dohrn) and Ascorhynchus (Hoek) they open on a small tubercle 

 situated on the fifth joint of the palp. In Nymphon, Hoek 

 describes them as opening by a small pore on the fourth joint 

 of the ovigerous leg. Dohrn failed to find them in Pycnogonum, 

 but in Phoxichilus, Phoxichilidium and Pallene he discovered 

 the glands appertaining to the palps, though the palps them- 

 selves have disappeared in those genera ; he has found the glands 

 also in Ammotliea, in larvae that have not yet attained their full 

 complement of legs. 



The males in nearly all cases are known to possess glands in 



