. Bulletin of the Essex Institute. Essex Institute; Natural history; genealogy. 125 ,b perceptible in the smaller specimens. By carefully turning back the outer edge of the girdle in the largest specimen, after removing the posterior plates, but without touching the animal with the dissecting knife, the anus was perceptible, with a pellet of faeces impacted in the opening. It is exactly in the median line behind as in the annexed sketch, very small, and not on a papilla. It is also a little higher up than in the other species. The "cancellated space" noticed by Mr. Emerton (as per no
. Bulletin of the Essex Institute. Essex Institute; Natural history; genealogy. 125 ,b perceptible in the smaller specimens. By carefully turning back the outer edge of the girdle in the largest specimen, after removing the posterior plates, but without touching the animal with the dissecting knife, the anus was perceptible, with a pellet of faeces impacted in the opening. It is exactly in the median line behind as in the annexed sketch, very small, and not on a papilla. It is also a little higher up than in the other species. The "cancellated space" noticed by Mr. Emerton (as per notice in Ann. Mag. Nat. Hist., Mar., 1874) on each side behind the branchiae is a fold or groove containing the ovarian fenestrse. There were in this specimen three fenestras on each side, but according to Dr. Carpenter the number is variable, Prof. Verrill having counted from four to six in some specimens. These fenestras in this species are more complicated than in most chitons which I have examined. I have never been able to satisfy myself that c'' there is a true oviduct, and it may be that ., , , . . ,<. . , a, a, fenestrse; b, anus; c, the ova are dehiscent in the perivisceral branchiae;/,foot; ^girdle. cavity and may be expelled through the fenestrae, as they are through the analogous "oviducts or segmental organs " of brachiopods. The fact that the ovarian openings are not simple apertures, was noticed by me in dissecting chitons in 1869, but I am not aware that attention had been previously called to this fact in print. Their posi- tion had been previously known, but it is not uniform in all chitons. In some the fenestrae are close to the anus and single on each side, and it has been stated that the ovary of one side is sometimes abor- tive. This last I have not yet observed in any species which I have Field Meeting at West Newbury, Thursday, July 16, 1874. The meeting this day was very pleasant, and in many of its features different from the us
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