B. Pseudoparasiten, Limulus-Commensalen. ]^21 



leaflets witli the plane side. The lower side of the capsule is Hat, the upper convex, as 

 shown in a side view, F 4. When the young escape they find their way out by the free 

 end of the capsule, which is ruptured as represented in FT. They are scattered all over 

 the branchial leaflets and on both sidcs of them." "On the specimen of Limuhis examined 

 by nie there were three well-marked types of egg capsules. The first represented in F l — 4, 

 enlarged sixteen times, measured about a twelfth of an inch, or about a line, in length, and 

 usually contained from tAvo to four embryos." "The second form, represented in F 5 — 7, 

 enlarged sixteen times, is riiuch smaller but similar in structural features to the preceding. 

 The capsules measure about one-twenty-fifth of an inch in length, and contain usually two eggs 

 of embryos. At first the ova occupy each one of the ends of the capsule, as shown in F 5, 

 but after the young worms have developed somewhat they usually lie along side of each other 

 lengthwise of the capsule. They frequently change positions, however, at this stage, and it 

 sometimes happens that there is but one embryo in a capsule. The ova of this, like the 

 preceding species are nearly opaque, and the walls of stomach in like manner are composed 

 of very dark granulär protoplasm. — The next form of capsule observed, is that represented 

 in F 9, enlarged sixteen times. . . . These, as stated before, were never seen to contain more 

 than one embryo, and measure over an eighth of an inch in length. The egg is not so 

 darkly pigmented as in the otlier forms." 



Ryder beschreibt dann die zu dieser Coconform gehörige Art. Da er in Folge falscher 

 Orientirung des Objeetes den Schwanz für den Kopf hielt, bezeichnet er diese kxt irrthümlich 

 als augenlos. Diesen Irrthum hat schon Hallez (127, 128) berichtigt. 



Weiterhin bemerkt Ryder: "I do not propose to name the species, as these supposed 

 distinct life histories may, after all our endeavors to separate them, be only phases of the 

 same thing. Sure points of distinction can only be got by a more thorough study of these 

 interesting types than I have been able to bestow upon them, and I leave them here in the 

 hands of such helminthologists as may be disposed to give the subjets of this notice further 

 attention." 



Fast gleichzeitig mit Ryder machte Gissler (1(»C) folgende Angaben über die Cocon- 

 formen der Bdellouriden : "The egg-cases were of various sizes, by far the greatest number, 

 however, being 3,50 mm in length (excluding the stem) by 1,50 mm in width. They were 

 plano-convex, the latter anteriorly, the former towards the gills. They consisted of a brown, 

 homogeneous, thick and leathery mass, either ovoid or cup-shaped, some of them having a 

 sort of a lid on their tip. — Within many of them were the young Planarians, free, moving 

 about, from one to three individuals in each capsule, in other the same were again enclosed 

 within a similar oval case without stem, and again others were found with there tip broken 

 oft' and empty. The greater number of them were covered around their tip with bluish 

 (colorless in alcohol specimens) ten-pin-shaped tubes with open tips. As these tubes were 

 invariably on or near the tip of the capsules only, they cannot be taken for parasitic organisms, 

 but may presumably be openings for an exchange of oxygenized water for the enclosed 



Zool. Station zu Neaiiel, Fauna und Flora, (!oIf von Neapel. TiiL-Imleu. 16 



