CIRRATTTLnLE. 241 



Cunningham 1 (1888) describes three longitudinal cords as occupying nearly the whole 

 cavity of the dorsal blood-vessel, the cords occasionally anastomosing. They have no con- 

 nection with the walls. These are the heart-bodies. 



De St. Joseph (1894) makes two great divisions of the family, viz. (1) Cirratulids 

 devoid of large prehensile tentacles, and (2) those having such. In the first are (1) Cirra- 

 tulus, in which the tentacles appear at the same time as the branchiae ; (2) Audouinia, in 

 which the segments bearing the tentacles are preceded by a variable number of segments 

 with lateral branchiae ; (3) Girrinereis, which has no lateral branchiae and no tentacular fila- 

 ments. He remarks that the tentacular filaments of Cirratulus and Audouinia do not differ 

 materially in external appearance from the lateral branchiae, and he disagrees with Clapa- 

 rede's account of their structure. This, however, had been previously alluded to by 

 Cunningham and Ramage, 2 who describe the characteristic groove of the tentacles, with the 

 nerve-strand at the base of the ridges and the presence of a single blood-vessel, whereas in 

 the branchiae two blood-vessels are present, viz. one at each pole in section with an 

 accompanying nerve-twig. 



In De St. Joseph's second division are, amongst others, Dodecaceria, Heterocirrus, and 

 Chsetozone. 



After Marenzeller, he also utilises the bristles as aids in classification. Thus in the 

 first group only capillary bristles appear in the two setigerous papillae, in the second group 

 capillary bristles occur throughout in the dorsal division, whilst crotchets are present in a 

 certain number of the ventral papillae ; and in the third group there are capillary bristles 

 and crotchets in a certain number of both divisions. 



An important memoir on the epitokous forms of the Cirratulidae by Professors Caullery 

 and Mesnil 3 appeared in 1898. In Dodecaceria concharum they found a small pelagic 

 epitokous form and a large sedentary epitokous form, besides the ordinary type, and the 

 masterly manner in which the authors treat the subject morphologically and physiologically 

 is worthy of all praise. They trace the initiatory changes, the completion of the transfor- 

 mation externally and internally, and compare the condition with that in other Cirratulidae. 

 In their form A (the ordinary type) the eggs are bluish and some are developed in the 

 coelom of the female, and gain the exterior through the segmental organs. They also 

 think that this form is parthenogenetic as only one male was found. In this connection it 

 is noteworthy that Cirratulus chrysoderma, Claparede, is stated to be viviparous, the young 

 occurring in the body-cavity of the parent. 4 In the young there are eyes, but they by-and-by 

 disappear. The adult has fifty segments, and cysts of Distomes were found in it. In 

 form C the ova, which are developed in autumn, are the smallest of the three (130/x, and 

 in the pelagic form 90^) and of a brownish yellow colour. They find exit by the segmental 

 ducts, which open in the middle of mucous glands. Of this series only females were met 

 with and they may be parthenogenetic. The colour is pale coffee, and the stout crotchets 

 are similar to those of A, only they have no spike at the base of the terminal excavation. 

 The development of the mucous glands is a prominent feature. It is probable that C 



Quart. Journ. Micr. Sc./ vol. xxviii, n.s., p. 265, pi. xviii, fig. 21. 

 Trans. Roy. Soc. Edinb./ vol. xxxiii, p. 644, 1888. 

 Annales PUniversite Lyon/ Fasc. xxxix, pp. 1 — 192, pis. i— vi. 

 'Zeitschr. f. wiss. Zool./ Bd. xix, p. 192. 



154 



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3 c 



