Miscellaneous. 447 



liens " of Perrier, nearly allied to Plutellus, and more nearly still to 

 Pontodrilus. To obtain a fairy spectacle it was sufficient, in the 

 evening, especially when the weather was damp, to kick or scrape 

 the gravel on the walks ; a multitude of luminous specks, of a fine 

 opalescent green, were at once lighted up. These specks were of 

 unequal dimensions : the largest produced a light as bright as that 

 of our glow-Avorras, and visible even in a room lig-hted by a good 

 lamp. When one of these specks was taken and rubbed between 

 the hands, both palms were soon rendered luminous. In the vicinity 

 of each phosphorescent sjieck, or of each luminous streak, a small 

 earthworm was found, which, more often than not, showed no 

 injury, in spite of the rather rough treatment employed to 'dis- 

 cover it, 



Photodnlus ]iliosplioreus\La& a length of from 45 to 50 millimetres, 

 with a width of I'o millimetre (i millimetres in the clitellian region). 

 It has about 110 segments. Its colour is of a rosy grey, orange at 

 the cingulum. The skin is sufficiently transparent to allow the 

 internal organs and an abundant vascular system to be seen. The 

 setge are short and bent ; but, instead of being in pairs as in most of 

 the Lumbricidae, they are distant from one another as in the Ponto- 

 drili. They form, accordingly, eight nearly parallel longitudinal 

 rows ; the two lower ventral rows are very near together in the 

 anteclitellian part, and the space which separates them scarcely 

 exceeds the width of the nervous chain. 



The cephalic lobe is I'ounded, and does not encroach upon the buccal 

 segment. Between segments b and 9 (the seventh and eighth setigerous 

 segments), on the lines of the lower ventral setse, may be seen the 

 orifices of the single pair of copulatory pouches. This is homologous 

 with the second pair in Pontodrilus. The cingulum begins towards 

 the superior third of the thirteenth segment, and occupies the 

 fourteenth, fifteenth, sixteenth, and seventeenth segments : this last 

 is very much shorter than the preceding ones. The fourteeuth seg- 

 ment contains the female genital apertures on the lines of the lower 

 ventral seta3 and a little above these setse. The male genital orifices 

 are on the eighteenth segment. The segmental organs only exist 

 below the fourteenth segment, and open externally at the upper 

 limit of each segment outside the lines of the superior ventral setse. 



The digestive tube commences with an exsertile part (proboscis), 

 which the animal evaginates and draws back alternately, rather 

 slowly, when it is subjected to the action of chloroform. In these 

 backward and forward movements, on the lower surface of the 

 buccal segment, a tuft of long transparent filaments may be seen to 

 project, sometimes finely striated transversely and of an extreme 

 slenderness. These setiform elements, which are much longer than 

 the cephalic lobe and very flexible, have not, to my knowledge, been 

 noticed in any Lumbrician. Must they be regarded as homologous 

 with the cjdindrical bacilli described by Perrier in the interior of 

 the hypodermis of the Pontodrili ? or are they really muscular fibres, 

 ruptured and dissociated by the reagent ? 



