234 46 



Combining the descriptions of the aboye-named authors the male may be 

 described as follows. 



The body has exactly the form of that of the female, the skin is softer and more 

 hyaline. Earlier authors have only rather cursorily studied the wheel-organ, but Weber has 

 shown, that it possesses five lobes, situated dorsall5- and equipped with rather long cilia, but 

 they are not so well developed as in the female. Whereas the wheel-organ in the female is 

 almost triangular with a deep notch ventrally and medially, the triangle in the male is much 

 lower O^EBER. Pl.vte), the borders equipped with a series of long cilia. The mouth is closed, 

 of the alimentary canal only a band remains, the function of which is only to support the 

 testis. In it yellow or brown bodies, most probably fat oil, are found (Pl.\te). The muscle 

 system is highly developed; the transversal muscles are numerous (Weber); of the longitudinal 

 muscles, the strong retractors of the wheel-organ, the muscles of the foot, and the trans- 

 versally striped muscles of the penis, are especially mentione:!. The nervous system consists 

 of a large brain giving off two ner\"es for the dorsal antenna; lateral antennæ are only observed 

 by Plate. On the brain a circular light-refracting but not red spot is regarded as the ej-e. 

 Of the excretory system the tv\-o long canals equipped ^\•ith four vibratile tags are observed; 

 the canals possess two openings one upon each side of the penis; the openings are round 

 and surrounded \\ith short and stiff cilia (Plate and Weber). There is no commissure between 

 the canals and in accordance with Pl.\te and Weber but in contrast to earlier observers no 

 contractile vesicle; the foot glands are in accordance with those of the female. The testis is 

 piriform enveloped in a thick muscular layer (Cohx, Weber not Leydig). It is fixed to the 

 body wall by means of three pairs of ligaments; the base of it is longitudinally striated; at 

 this base the penis is attached; it consists of a sheath transversally striated by fine and 

 numerous muscles; it is cylindrical and long. The external orifice is surrounded by a crown 

 of short cUia; in this thick sheath lies the real penis, a ver\- thin pointed organ (Weber). .\t 

 both sides of the penis two glands commonly regarded as prostata glands are observed. On 

 both sides of the testis and above it opaque granular masses, according to Cohn", Weisse and 

 Weber remains of the yolk, according to Leydig urin concrements, are observed. Size of fe- 

 male 4—300," of male 200— 250". Time March— May. 



Description: Body form almost that of the female, but the dorsal side some- 

 what more vaulted. Cuticula extremely thin and the whole animal extremely hyaline. 

 Foot short, confluent with the body; two short acute toes. Wheel-organ highly 

 differentiated, still not so much as that of the female. The ciliary wreath (couronne 

 postorale of the authors) constitutes a band of short, very fine cilia, in which I 

 have not hitherto been able to point out the strong sensorial hairs mentioned by 

 DE Beauchamp in the wreath of the female. It encircles a disc somewhat ventrally 

 placed. This disc, which is triangular in the female, is of a somewhat different 

 form in the male, the ciliary wreath on the ventral side only forming a great curve. In 

 the female the mouth is situated in a furrow, hing a little above that point where 

 the tv\o sloping sides of the ventral contour of the disc meet each other; the furrow 

 and part of the disc above this is covered with fine cilia. Where the mouth opening 

 is situated in the female, there is a cupshaped cifia-covered elevation, carrying on 

 its top about 10 strong setæ. The other part of the disc seems to be destitute of 

 any cilia coating, but carries strong setæ (raembranelles de Beauchamp) in an 

 arrangement similar to that in the female, though somewhat reduced. On the disc 

 nearest to the dorsal side stands a series of five elevations, of which the median is 



