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Straits of Macassar. Once in tlie Chinese Sea, they would soon reach 
Japan ; and thence, by the help of the great current of Tessan (the * Black 
River ’ of the Japanese), they would easily make the tour of the North 
Pacific along the shores of Kamtschatka, the Aleutian Islands, and North 
America, as far as the south of California. 
M. Trouessart considers that the genus Zalophus furnishes a proof of this 
migration, — it occurs on both sides of the Equator, namely, at Melville 
Island, Japan, California, and throughout the northern part of the Pacific. 
Currents have probably acted an important part also in the dispersion of 
other forms of Seals,-— thus a species of the genius Pelagius, generally con- 
sidered almost peculiar to the Mediterranean, has lately been detected in the 
West Indies ; and M. Trouessart remarks that the Monk Seal (Pelagius 
monachus) of the Mediterranean is known to pass out through the Straits of 
Gibraltar and to occur on the north-west coast of Africa, and as far as 
Madeira and the Canary Islands, so that some individuals of this species may 
easily have got caught by the equatorial current and carried away to the 
West Indies, where they have given origin to a new form ( Pelagius 
tropicalis ) . 
Macrorhinus is the only genus of true Seals occurring on both sides of the 
Equator, and Mr. Allen places the starting-point of this type in the Northern 
hemisphere. M. Trouessart remarks that the genus is only found there now 
at one point on the Californian coast, while it abounds on all the shores of the 
Southern hemisphere, and he is inclined to place the head-quarters of the 
type about the Island of Juan Fernandez, which is now one of their principal 
stations, and to assume that they were carried by the oceanic currents 
through a long detour by the Polynesian Islands to California. — Comptes 
Pendus, May 9th, 1881. 
Mollusca and Vermes . — At the close of an investigation of the embryology 
of the Pulmonate Mollusca (Archives de Zoologie Experiment ale, 1880), 
M. Hermann Fol indicates certain conclusions at which he has arrived with 
respect to analogies existing between the Mollusca and Vermes. He regards 
the larvae of the Mollusca as comparable only with the cephalic portion of 
the larvae of Annelids, or with an entire Rotatorian. The Mollusca are not, 
in his opinion, segmented animals whose segments have been subsequently 
fused together, but animals that remain simple and never present even a 
rudiment of the metameric budding of the Annelids ; whilst Rabl considered 
that there was an analogy between the very young Molluscan larvae and a 
worm with three metameric larvae. In conclusion, Fol remarks how greatly all 
recent investigations are in favour of the re-establishment of the Linnean 
class of Vermes. He thinks that the general result of recent embryogenic 
researches tends to the establishment of three great divisions of animals : — 
(1) the Vermes, Bryozoa, Brachiopoda, Mollusca, and Echinodermata ; (2) 
the Arthropoda ; (3) the Chordonia (Tunicata and Vertebrata). — Kosmos , 
1881, Band ix. 
Olfactory Organs of Insects. — M. Gustav Hauser has investigated this 
subject (Zeitschr. fur wiss. Zool., vol. xxxiv. p. 367), and arrived at the 
conclusion that the sense of smell in insects is seated in the antennae. Glass 
rods moistened with oil of turpentine or acetic acid were presented to a 
great number of insects, which showed very clearly their perception of these 
