146 T. H. JOHNSTON. 



occurs, as far as I know, in Cyclorchida, but this genus 

 possesses a great number of these vesicles (about ninety), 

 and a double circlet of rostellar hooks of a characteristic 

 form viz., there is a powerful base and a small hook part. 

 There is thus very considerable and important differences 

 between these two genera. Though the cirrus sac is beset 

 with strong spines in both, yet the details of this organ are 

 different in each genus. 



The other nearly related genus is Acanthocirrus, Fuhrm. 1 

 in which there is no mention of the arrangement of the 

 rostellar hooks, consequently we cannot compare in this 

 direction. The male organs however are quite different to 

 those of Clelandia, since the testes, though few in number, 

 are not arranged around the female glands but are situated 

 behind them in the posterior half of the segment. The 

 cirrus and vagina show considerable resemblances to those 

 of our genus, but the large characteristically shaped spines 

 lying in special pouches at the base of the cirrus in Acantho- 

 cirrus are not present in Clelandia. 



It appears, therefore, that the new genus lies between 

 Cyclorchida and Acanthocirrus and approaches more nearly 

 to the former, if we exclude the shape and arrangement of 

 the rostellar hooks. It is worth noting that the only species 

 of the former genus, viz., C. omalancristrota, Wedl., and 

 that two out of the three known species of the latter genus, 

 viz., A. macropeus, Wedl., and A. cheilancristrota, Wdl., 

 occur in birds belonging to the Oiconiiformes (Storks and 

 Cranes). 



Type species: — Clelandia parva, Jnstn., from the intestine 

 of Xenorhynchus asiaticus, Lath.? 



Locality: — Jervis Bay, N. S. Wales. 



1 Fuhrmann, Centrb. f. Bact., Orig., I, xlv, 1908, p. 527; and in Zool. 

 Jahrb., Suppl. Bd., x, Heft 1, 1908, p. 63. 



