Miscellaneous. 199 



On the Nepliridia o/Branchiobdella varians {var. astaci). By D. JN^. 

 VoiNov, Morphological Laboratory at Bucharest. 



During the year 1895 T have studied the excretory apparatus of 

 BranchiohdelJa varians (var. astaci), a parasite which I have found 

 in great quantities occasionally upon the branchiae of crayfish 

 brought to the market of Bucharest. 



Despite the labours of Henle, Keferstein, Dorner, Lemoine, Voigt, 

 &c. on the general organization of this animal, the excretory organ 

 is still insufficiently understood. All that was known was that 

 each nephridium is composed of five regions, which are from within 

 outwards: — (1) the vibratile funnel; (2) the red gland (of Odier); 

 (3) the canalicular chain : (4) the excretory canal (efferent) ; (5) the 

 terminal vesicle. The structure and true relation of these various 

 parts were, however, unkuown ; in a word, no general interpretation 

 of this complicated organ has ever been given. 



I have studied the excretory apparatus by transmitted light in 

 the living animal and by means of microscopic sections ; the results 

 arrived at may be briefly summarized as folio vvs: — 



The funnel is composed of a body — the funnel properly so-called 

 — and of a peduncle, which is a continuation of it. It is placed on 

 the ventral side of the animal, and opens partly into the general 

 cavity of the animal and partly into the red gland, with which it 

 communicates by the peduncle. This first part of the nephridium is 

 provided with a continuous ciliary covering, the movement of which 

 is towards the red gland. The form of the funnel so-called is that 

 of a cup with straight ciliated edges ; its longitudinal diameter is 

 0*10 niillim. and its greatest transverse diameter is 0"075 millim. 

 The funnel and its peduncle are capable of movement in all direc- 

 tions in the interior of the cavity of the segment around their base 

 of attachment. 



The red gland of Odier is a lobulated body, of a red-brown colour 

 in the adult animal. By reason of its structure and connexions I 

 have named it capsule, after the name of the corresponding region 

 in the nephridia of the Hirudineae. In this gland there are to be 

 distinguished two kinds of structures : — (1) a system of irregular 

 lacunae, communicating one with another, traversing it in all direc- 

 tions, and giving it a spongy appearance : (2) a system of regular 

 canals. The former belong properly to the capsule, being excavated 

 in its substance, whilst the latter only traverse it, establishing 

 communication between the capsule and the third part of the 

 nephridium, that is to say, the canalicular chain. 



The peduncle of the funnel opens into a lacuna of the capsule. 

 One of these lacunae, greatly enlarged, contains in its interior a 

 compact cellular mass, analogous to the contents of the capsule in 

 the Hirudineae. in which are gathered a quantity of pigmentary 

 granules of a red-brown colour. The flagella are fixed to the walls 

 of the lacunae, turned in all directions, thus indicating a great com- 

 plication in the direction of the movement of the lacunar fluid. In 



