100 Mr. H.J. Carter uii the Spermatolugti of a new species o/Nais. 



shape, wherever it goes, and whatever form it assumes ; which 

 pellicle, on hardening, takes on the form given to it by the 

 protoplasm, and thus the tubular prolongation is produced ; it 

 is, in fact, only an instance of the way in which all organic forms 

 are developed, viz. by the moulding power of the protoplasm, 

 which in this case, however, has lost its specific nature. 



Filar ia in Nais albida (fig. 50). 



Among the figures illustrative of this paper will be observed 

 one of a Filaria, which I frequently found singly and in variable 

 plurality in the peritoneal cavity of Nais albida, which worm, I 

 have already stated, was met with accidentally in a species of 

 Gloeocapsa that abounds with microscopic Filaria during the 

 rainy season. This Alga having been collected for this purpose, 

 I shall defer further mention of this fact than that which will be 

 found in the explanation of the figures, until I come to describe 

 these Filaria generally, which I propose to do on a future 

 occasion. 



Bombay, 24th April, 1858. 



EXPLANATION OF PLATES IL, IIL & IV. 



N.B. — Wherever the species from which the figure has been taken is not 

 mentioned, it must be assumed to be Naisfusca. 

 For the purpose of conveying some idea of the relative size of many 

 of the objects, they have been drawn uj)on a scale of l-12th to 

 l-5(j()0th of an inch, and their measurements given in 5600ths, 

 with the same view. 



Plate II. 

 Fig. I. I^aisfusca; natural size. 



Fig. 2. Ditto, proportionally magnified, showing — a, oesophagus ; b, testes; 



c, oviducts, or so-called "uteri;" d, ovisacs; e, rejiroductivc band; 



/,/, intestine ; g, segmental organ; h, continuation of worm. 



(The central part of this figure is not fiUed-iu, to save trouble.) 



Fig. 3. Ditto, anterior part, still more magnified, showing — a, oesophagus; 



b, b, b, floating-cells in the peritoneal cavity; c, testes; (/, orifices 

 of si)crmatic ducts; e, ciliated o])enings of e', the so-called " fal- 

 lopian tubes ;" /, oviducts, or so-called " uteri ;'' g, vaginal open- 

 ings of ditto ; h, h, ovisacs ; i, fioating-cells in cavity of ditto 

 (sec the same also, fig. Via, e, more magnified); k, ditto, agglo- 

 merated (afterwards forming granular masses) ; /, ditto, caudate 

 (for a more magnified view, see fig. Ki a,f, d, e); m, intestine, 

 covered with hepatic cells; h, segmentid organ; o, ciliated or 

 internal opening of ditto ; p, elliptical jiortion of ditto; q, exter- 

 nal opening of ditto; r, external or celhdar sheath; s, internal 

 or structureless sheath ; t, reproductive band. 



Fig. 4. Magnified view of cirrus and setae: «, seta;; i, bulb of ditto; 



c, cirrus. 



Fig. 5. Cells of reproductive band, diffiuent in form, about 2-5()()0ths of an 

 inch in diameter when si)herical (drawn on a scale of l-12th to 



