18 



the free ramus was inserted, and gradually narrowing in a slightly 

 curved line towards the end. At the end there is a small, 

 stout, triangular tooth, standing at right angles to the ramus; the 

 outer third of the inner edge has a number of small, irregular, up- 

 right teeth; the second third has eight teeth of different sizes, rang- 

 ing from 7-16 of an inch to less than 1-16 of an inch, inclined at an 

 angle of about forty-five degrees; the inner th ; rd of the ramus is 

 smooth. The larger teeth are finely serrated on the inner edge; sur- 

 face smooth, length of specimen 2% inches, greatest width 7-16 of 

 an inch. 



2. A detached impression of a rounded appendage found in the 

 water-lime, has been in the museum of the society for several years; 

 (Fig. 4), another fragment found last year preserves besides this ap- 

 pendage the last eight articu- > 

 lations of the abdomen, thus / < V^-r-"-'"''-. -\ 

 proving it beyond doubt the / "•"-" V: V- :-„v ;V \ 



... / r*.v.-p •• 



tail of a water-hme crusta- 

 cean. It is oval and has a 

 distinct ridge running down 

 in the middle. The interior ) 

 portion of the specimen has 

 its surface covered with 

 small, pointed, scale-like 

 processes, quite distinct from 

 each other; the posterior two- 

 thirds of both margins are ir- 

 regularly serrated, the largest 

 tooth occupying the middle 



into which the dividing ridge terminates. This specimen is ^ 

 inches long and 2% inches wide; but a fragment of this tail has 

 been found, which, when restored, has a length of 6J4 inches, and 



Fur. 4 



