Videnskabelige meddelelser

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Videnskabelige meddelelser

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less densely (PI. I, fig. 1 1). With low power under the microscope

the pigment is seen as an irregularly winded band of brown colour,

stretching along the body.

As far as can be seen in my specimens the æsophagus ap-

pears to be of a peculiar structure. Possibly this appearance is

owing to the surrounding cells which are hiding the real faet, but

in any case nothing is seen of the usual transverse striation char-

acterizing in most of the freeliving Nematodes the structure of the

æsophagus. A figure resembhng that given by Stei ner of Enc/ie-

lidium polare (1. c Taf. 16, f. 28 c.), the æsophagus of which is

like that found in the genus Phanoderma is not seen in my spec-

im.ens.

A ventral gland is present, situated at some distance behind

the base of the æsophagus, alongside the intestine. This gland

consists of a single cell which also forms the excretory duet run-

ning forwards and opening on the ventral side of the „neck" of

the animal somewhat caudad for the eyes. In a specimen, the length

of which mesured 4,3 mm, the gland was situated 297 /< behind

the front end. The excretory duet opens by means of a very thin

excretory tube issuing from an ampulla in the foremost part of the

body (PI. I, fig. 1). The canal itself as well as the hindmosi part of

the ampulla is — as far as it has been possible to ascertain in

my preparation — of a protoplasmatic structure and a part of the

secernating cell itself; the excretory tube and the foremost half of

the ampulla is, on the contrary, a formation originating from the

cuticula. PI. I, fig. 1 shows this case; the canal is of quite the same

protoplasmatic structure as the cell and this structure can be fol-

lowed unto the ampulla, where the duet extends and forms two

lips enclosing the hindmost part of the ampulla. This case is, for

the rest, not unique among freeliving Nematodes; I have observed

the like in other genera.

As to the genital apparatus I have nothing to add to Eberth's

description; I shall only remark, that the ^2 anal „Hocker" men-

tioned by this author are presumably not to be considered as veri-

table masculine papillæ but only as projections owing their occur-

rence to the stiff cuticula in the strongly bent hind-part of the

body; a settling of this question is scarcely possible on preserved

material but I suppose it will be easy on living specimens.

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