246 SUMMARY OF CURRENT RESEARCHES RELATING TO 



may be called the scleropyge and tlie sclerorhynclius ; they are 

 modifications of peculiar structures found in Asjpidosiphon ; the 

 scleropyge is probably used in burrowing in sand, and has the body- 

 cavity continued into it, but is imperforate ; the stout sclerorhynchus 

 is open anteriorly to serve as the orifice of invagination of the pro- 

 boscis. After some notes on the internal organs, in which the 

 continuous nature of the long muscles of the body, the presence of 

 four retractor muscles to the introvert (proboscis), and the absence of 

 bush-like organs on the rectum are reported, the author gives a 

 definition of the Sipunculoidea, slightly altered from E. Selenka, and 

 concludes with a key to the genera of the group. Golfingia is not 

 far removed from Aspidosijphon, but differs in the form of its sclerites, 

 in the disposition of the retractor muscle, and in the character of the 

 oral tentacles. 



Polychseta of Dinard.* — M. de Saint Joseph endeavoured, while 

 at Dinard, to fix the local fauna, and to describe new or imperfectly 

 known species. He has found 186 species of Polycheeta, 44 of which 

 are as yet known only from that locality, 87 are found in the 

 Mediterranean, and 42 in the northern waters. A number, especially 

 of the larger forms, were found to be stationary. Among the new 

 species found, but here only very briefly indicated, are Paractius 

 mutahilis, which preserves the larval form when adult, and though 

 only 3 • 80 mm. long has about 800 denticles on its jaw ; Lahro- 

 rostratus parasiticus g. et sp. n. is a small Lumbrinereid which lives 

 parasitically in the body of several Syllidese ; Leptonereis vaillanti ; 

 Sderocheilus csecus. The author has been able to prove that Eury- 

 syllis reproduces by a single stolon, and that Myrianida maculata may 

 have fifteen male stolons ; the so-called T-shaped glands of Syllideae 

 appear to be not glands, but water reservoirs. Autolytus was found 

 to reproduce thus : there is first a single male or female stolon 

 formed by fission, which has three regions ; there then appears a 

 second and perhaps other similar stolons, and then others, which 

 are shorter, and divisible into two regions, and finally, a chain of 

 several stolons, placed end to end. 



Worms in Ice.t — Prof. J. Leidy describes some worms found in 

 ice which was full of bubbles of air and water. He considers that the 

 worms remain in a torpid condition in the water-drops. When the 

 ice was melted, the worms soon died. He gives the name Lumhricus 

 glacialis to the worm (though the description indicates some other 

 genus, if not a limicolous form). Length 4 to 6 lines. Genital organs 

 between the segments four and seven ; setse in four bundles of three 

 each, in every segment after the first. 



New Mode of Development in Nematodes.! — Dr. 0. v. Linstow 

 fully describes a new Nematoid which is found in the intestine of 

 Triton alpestris, and more rarely T. cristatus ; its life-history may be 

 divided into seven stages — the embryonic form, the water-larva, the 



* Comptes Rendus, ci. (1885) pp. 1509-12. 



t Proc. Acad. Nat. Sci. Philad., 1885, p. 408. 



X Zeitschr. f. Wiss. Zool., xlii. (1885) pp. 708-17 (1 pi.). 



