198 DR. G. S. BRADY OX THE [Feb. 1, 



of British Ostracoda' as a variety of C. Candida, the only 

 examples then known to me being a few dried shells found at 

 Gravesend and sen£ to me by my friend Professor T. Rupert 

 Jones. I have since taken it abundantly in the river Coquet near 

 the Hermitage at Warkworth, and in Hickling Broad, Norfolk, 

 in ditches near Arundel and Felixstowe, and in a pool above high 

 water at Penmaenmawr ; and I have specimens taken by the late 

 Dr. D, Robertspn in Lough Neagh. In all these places the water 

 probably becomes slightly saline owing to the influence of sea- 

 spray or perhaps occasional tirlal overflow. The shell of this 

 species is liable to be infested with circular papilliform excrescences 

 which are probably the encysted stage of a trematode worm 

 (PL XX. figs. 9, 10, PI. XXX. figs. 1-4). A portion of the shell 

 with the circular cysts is shown in fig. 10, and in the interior 

 of two of the cysts may be seen the coiled young worm. And 

 within the valves is occasionally to be found a fully developed 

 Avoim, which has been examined for me at the Armstrong College, 

 Newcastle-on-Tyne, by Miss M, V. Lebour, M.Sc, now of Leeds 

 University. This is roughly represented in fig. 9. Miss Lebour 

 pronounces it to be one of the group Acanthocephala belonging 

 ifco the genus Xeorhyncfius, probably JOT. claviceps Zaddach (see 

 PI. XXX. fig. 5). Her remarks on the specimens — which she 

 kindly allows me to reproduce here — are as follows : — 



" Jt is about 1 mm. long with a thick skin and a retractile 

 proboscis armed with few spines in number and arrangement the 

 same as in i\ r . claviceps. The most anterior spines are large, brown- 

 ish, and much recurved, the two rows of smaller spines behind these 

 are simpler and quite clear and colourless. In the thick sub- 

 lenticular layer of the skin a few giant nuclei can be distinguished 

 as in JV. claviceps. All the specimens seen appear to be males. 

 There is only one testis instead of two as in JV, claviceps, which 

 occurs near the centre of the body, and an indistinct vas deferens 

 runs down from this, becomes more distinct where the glands 

 appear, and opens at the extreme posterior end. The retractors 

 of the probosicis are conspicuous, as are also the peculiar structm-es 

 knoAvn as the lemnisci. Four specimens occurred in one Candona 

 and single specimens in several others. Small Crustacea or water 

 insects are the usual hosts for these Acanthocephala, and in the 

 family ]s eorhynchidce. the larval forms are sexually mature. The 

 adult N. claviceps lives in the carp 5 Cyprinus carpis, and the larval 

 form in the larva of tSialis lutaria, one of the Neuroptera 

 (Cambridge Natural History, vol. ii. p. 1 85). It is interesting to 

 get this species in a new host, for it does not appear to have been 

 noticed in Candona before." 



Candona neglecta G. 0. Bars, (Plate XXI. figs. 1-8.) 



1887. Candona neglecta G, O. Sars, Nye Bidrag til Kundskaben 

 om Micldelhavets Invertebratfauna, p. 107, pi. xv. 

 figs. 5-7, pi. xix. 



1866. Candona Candida G. S. Brady (in part), (1) p. 383. 



