128 CH^ETOPTERTTS VARIOPEDATUS. 



When removed from its tube the annelid lies coiled on the bottom of the vessel, the 

 tail being curved to the middle region. When disturbed in its tube the two tentacles are 

 sometimes protruded. 



In the tubes on the south coast of England Nychia cirrosa accompanies this species 

 as a commensal, and Ray Lankester gives Harmothoe sarinense ( = Lagisca floccosa, Sav.) 

 and H. Malmgreni (= H. setosissima, Sav.) in the same tubes at Herm, whilst Hornell 

 found the latter form at Beaumaris. 



Reproduction. — At Naples, where it is termed " Ricce rinte o tube," the period of 

 sexual maturity ranges from May to September (Lo Bianco). 



The larva (which Lo Bianco found at Naples from February to July) is mesotrochal, 

 with a ciliated ring round its middle, the region in front of the ring giving rise to the 

 anterior division of the body, whilst that posterior to it develops into the two succeeding 

 regions. 



De Quatrefages (1865) formed a new species for examples from the coast of 

 Normandy, but such do not differ from the common forms, and the same may be said of 

 his C. Leuckarti from the Adriatic. 



Dr. Baird, in 1864, described this as a new species under the name of G. insignis, but, 

 as his specimens show — for he was so kind as to send examples — it was only the 

 confusion of previous authors which caused the ambiguity. 



R. Leuckart pointed out that authors have mistaken the dorsal for the ventral 

 surface of Chxtopterus. He found Modiola parasitic in its tube. He was inclined to place 

 it with the Ariciinas, since it agrees in the rudimentary development of the head, and has 

 a somewhat similar body with appendages. Its ventral hooks are akin to those of the 

 Capitellidse, yet Chmtojpterus is a higher form. 



Lespes 1 (1872) gave a sketch of the structure, apparently of the common species, pro- 

 cured on the shores of Provence, which form, however, he terms 0. brevis. He found no 

 trace of a circulatory system, and the male segmental organs which are in the posterior 

 segments have the shape of a grooved funnel, which joins a tube opening externally, 

 whereas in the female it is an opaque organ without an internal funnel. 



A careful account of the phosphorescence of this form was given by Panceri (1875), 

 including the phosphorescent glands of the pinnules and other parts, his conclusion 

 being that the luminosity resided in special cells of the external epithelium, especially 

 in the glands of the pinnules and pyriform elements of the ciliated epithelium elsewhere. 



Cosmovici (1880) states that the organs of Bojanus are closely connected with the 

 segmental organs, and that they possess external apertures, but apparently the only 

 internal aperture is that of the segmental organ with which it communicates, and which, 

 he states, opens into the intestine. These organs occupy the three dilated portions of the 

 middle region. The author, thus, was in error in regard to the structure of the parts. 

 He describes the genital glands as in the form of a loop in the same region of the body, 

 one end being fixed to the intestine, the other free. The ova or sperms are shed into the 

 coelom and find exit by the segmental organs. These organs — a pair in each segment — 

 likewise occur in the posterior region of the body in the same close connection, the organ 



1 f Ann. Sc. nat./ 5 e ser., t. xv, art. 14, p. 63. 



