Miscellaneous. 149 



the outer branch, which is wide and furnished on its upper margin 

 with six spinous hairs, has in its centre a large bilobed gland ; the 

 inner branch is very narrow, and terminates in two stiff hairs. 

 The other thoracic feet (two to five) are rudimentary and gradually 

 diminish ; the genital segment is rather wide, while the three follow- 

 ing abdominal segments are very narrow ; the furca bears upon 

 each of its branches one long and four smaller setse. 



The male, which is much rarer than the female, is smaller and 

 of a narrower form, resembling that of Cyclops. The first and 

 second pairs of thoracic feet chiefly furnish the differential sexual 

 characters. The inner branch of the first biramose foot is wider 

 than in the female and furnished with seven hairs on its free mar- 

 gin ; the second pair are strongly developed and terminate in two 

 long branches, of which the outer one is fringed with eleven setse 

 (one terminal and five on each margin), while the inner one has 

 only eight setae upon its inner margin. The other thoracic feet are 

 rudimentary, as in the female ; the genital segment bears a sixth 

 pair of aborted feet, which would seem to confirm Delia Valle's 

 opinion that this segment is thoracic. Clans regards it as the first 

 abdominal segment. 



Oviposition takes place from the beginning of May to the end of 

 September ; the young attach themselves at the extremities of the 

 arms of the Ophiuran, and approach the disk as they grow. Two or 

 three egg-bearing females are sometimes found on the same Am- 

 phiura. After hatching the empty sacs adhere for a time to the 

 abdomen of the female. 



The ova are of a fine ashy-green colour. Segmentation is com- 

 plete and unequal ; there is epibolism and formation of the meso- 

 derm by two primitive mesodermic cells, which originate from the 

 endoderm at the point of contact of the latter with the first exo- 

 dermic blastomeres. The nauplian embryo within the egg shows 

 the rudiments of four pairs of limbs besides the characteristic appen- 

 dages of the nauplius. The latter consist of a uniramous first pair, 

 the basal joint of which bears two simple setae and the terminal 

 joint two barbed setse, and of two biramose pairs. The upper 

 branch of the latter is furnished with one simple and two barbed 

 hairs ; the lower branch bears five barbed hairs in the first pair and 

 four in the second. Beneath each appendage there is on the margin 

 of the carapace and on each side a glandular mass. The anal extre- 

 mity is obtuse and furnished with two divergent hairs. 



At Concarneau, and especially at Fecamp, the Ccmcerilla is 

 frequently covered with a parasitic Ehizopod, which attaches itself 

 to the carapace, especially at the anterior margin. The author 

 names this PodarceUa cancerillce, gen. efc sp. n., and describes it as a 

 pedunculate Arcellian of which the peduncle adheres to the carapace 

 of the Copepod by a small discoidal expansion. The peduncle is 

 half as long again as the funnel-shaped cup ; both are composed of 

 an apparently chitinous substance ; the walls of the cup are elastic, 

 semitransparent, and irregularly notched at the margins, and within 



