A Bare Meliceriian. 167 



whose procession, or the appearance of such is seen to be in one and 

 the same direction from left to right when viewed in a neural 

 aspect, and that it is supplemented by a secondary range of more 

 minute cilia, whose procession is divided into two channels, ema- 

 nating from the under-side of the corona in its expanded condition, 

 and progresses, so to speak, in opposite directions, conveying the 

 captured particles to the mouth, where they are subjected to the 

 scrutiny of a bilobed ciliated organ, situated immediately above it, 

 though, unlike the epistome of Steplianoceros, it is placed in a haemal 

 position, but it exercises a similar function in selecting the nutritive 

 particles from the general mass, and in rejecting others, as the 

 scrutiny may determine. This secondary range of cilia obtains, in 

 a more or less developed condition, in every individual member of 

 the Melicertians, whether it be Limnias, (Eeistes, or Lacinularia, 

 and it terminates in a process projecting from the ganglion side, 

 and in most, but not all of the members, it is supplemented by 

 a fabricating organ, which is employed in the construction of their 

 compound tunicles, an exceptional instance occurring in a little 

 Melicertian, which employs her voided excremental pellets to cover 

 the otherwise hyaline investment. This fabricating organ, in its 

 normal position, is also wanting in the instance of the elegant Form 

 which has induced these remarks, Plate XCVIII., Fig. 1, and in 

 bringing them to a close it will be only necessary to add that the 

 genus Melicerta must include all those members in which the 

 foregoing points are permanent, and that Limnias, (Eeistes, and 

 Tuhicolaria are essentially Melicertians, and will be referred to 

 as such ; retaining, however, their hitherto specific appellations as 

 for the sake of facility of recognition. 



Melicerta annulatus. 



My attention was first drawn to a vagina of this species, which 

 at a glance exhibited proportions differing from any hitherto known 

 Form, containing within it an ovum of a magnitude equally sur- 

 prising. I at once applied the micrometer, and for the moment 

 failed to notice the corrugations which, singularly enough, coincide 

 exactly with the 2U00th divisions of the micrometer; they occur 

 as little ridges formed around the circumference of the vagina, which 

 in all young, and young adults is perfectly hyaline, manifesting 

 a decided and brilliant orange tint, but seen at the two sides 

 when in proper focus they are rendered very distinct, the orange 

 tint becomes condensed into a deep carmine. How these ridges 

 become formed with such marvellous precision is a matter that must 

 strike all with wonder and admiration ; and although I do not feel 

 myself prepared at once to state anything definite as to their 

 formation, I can only suggest it as worthy of attention that the 

 anterior regions manifest a considerable and somewhat complicated 



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