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Show 530 ON A NEW SLUG OF THE GENUS JANELLA. [June 19, great weight to the separation of N. dubia from J. bitentaculata, the specific distinctness of which yet remains to be proved \ It will be as well, perhaps, to here state the sizes of the specimens I have received from Mr. Suter, as indicating possibly the average length which J. bitentaculata attains : these sizes are 32, 32, 40, 43, 45, and 48 millim. In a recent communication received from Mr. Charles Hedley, he states that he has seen J. papillata 53 millim. in length. M y largest specimen, in alcohol, measures 32 millim. Fig. 5. Digestive system of Janella maculata. (For lettering see p. 527.) The chief points of difference between J. maculata and J. bitentaculata may be summarized as follows :- The form and length of the free oviduct and penis, the shortness of the common duct, the form aud divisions of the hermaphrodite gland, the distinct form of the albumen-gland, and the minor differences in the liver, colour of the animal, and general flattened form of the whole of the body. In concluding this description I would remark that the whole family Janellidce requires revision. It is very desirable that we should have a series of coloured drawings taken from actually living specimens of each species and variety, with careful drawings of their anatomy. 1 Ann. & Mag. N. H. 1892, vol. ix. (ser. 6) pp. 169-171 ; Trans. New Zealand Inst. 1892, pp. 156-162; Journal of Malacology, 1894, vol. iii. p. 13. |