R T R T Order II. Bdelloida. Forms which swim and creep like a leech ; foot retractile, jointed, telescopic, termination furcate. Fam. 3. PHILODIXAD.E. Philodina, Rotifer, Callidina. Order III. Plotma. Forms which swim only. Grade A. ILLORICATA. Fam. 4. HTDATIXAD*. Hydatina, PMnops. Fam. 5. SYNCHJETAD^;. Synchxta, Polyarthra. Fam. 6. NOTOMMATAD.S. Notommata, Diglena, Furcularia, Scandium, Fleurotrocha, Distemma. Fam. 7. TRIARTHRAD.E. Triarthra. Fam. 8. ASFLANCHNAD.B. Asplanchna. Grade B. LORICATA. Fam. 9. BRACHIONID.E. Brachionus, Noteus, Anursea, Sac- culua. Fnm. 10. PTERODINAD*. Pterodina, Pompholyx. Fam. 11. EUCHLANID.E. Euehlanis, Salpina, Diplax, Mono- styla, Coliinis, Alonura, Mctopodia, Stephanops, Monocerca, M< ' <( igocerca, Dinocharis. Order IV. Scirtopoda. Forms which swim with their ciliary wreath, and skip by means of hollow limbs with internal locomotor muscles. Fain. 12. PEDALIOXID.E. Pedalion. The above list includes only the principal genera. There are, however, a number of forms which could not be placed in any of the above families. ABERRANT FORMS. . Trochosplixra asquatorialis (fig. 6, o), found by Semper in the Philippine Islands, closely resembles a rnonotrochal polychaetous Fio. 6. Various aberrant forms. A, Balatro taints (after Claparedc) : a, mastax. B, Sfiton nebalim (after Claus) : m. mouth ; vd, position of the aperture of the vas deferens. C, Urulia toru'ota : a, ciliated processes at the sides of the head representing cephaMroch : oc, eye-spots. I), E, and F, Apsilvs lentiforniit (after Mecznikow). D, adult ft-male with expanded proboscis : m, position of the month ; , lateral sense-organs. E. young free-swimming female. F, adult male. G, Trochosphtera miuatorialitt (after Semper) : m, mouth ; g, ganglion ; a, anus ; 6, velum ; oc, eye-spot ; c, muscles. larva while possessing undoubtedly Rotiferal characters. Mecznikow has described a remarkable form, Apsihis lentiformis (fig. 6, D, E, and F), the adult female of which is entirely devoid of cilia but possesses a sort of retractile hood ; the young female and the males are not thus modified. Claparede discovered fixed to the bodies of small Oligochaetes a curious non -ciliated form, Balalro calvus (fig. 6, A), which ha* a worm -like very contractile body and a well- developed mactax. As mentioned above, the ciliation is reduced to a minimum in the curious worm-like form Lindia (fig. 6, c). Seison nebalia (fig. 6, B), living on the surface of Nebalix, which was described originally by Grube, is the same form as the Saccobdclla nebalia, which was supposed by Van Beneden and Hesse to be a leech. It has been shown by Claus to be merely an aberrant Rotifer. Of the curious aquatic forms Icthydium, Chatonotus, Turbanella, Dasyditis, Ccphalidium, Chxtura, and Hemidasys, which Mecznikow and Claparede included under the name Gastrotricha, no further account can be given here. They are possibly allied to the Rotifera, but are devoid of mastax and trochal disk. The following are some of the more Important memoirs, Ac., on the Rotifera (1) Lceuwenhoek, Phil. Tram., 1701-1704. (8) Ehrenberg. Die Infutiontthierchen alt roiltommene Organitmen. 1838. (3) M. F. Dtijardin, Hit. Hot. det Zoophyte* Infutoiret, 1841. (4) W. C. Williamson, "On Melicerta ringeni," Quart. Jour Micr. Sci., 153. (6) Ph. H. Gosse, "On Uelicerta ringeni," Quart. Jour Micr .1-1. , 1853. (6) T. H. Huxley, " On Lacinularia locialit," Trant. Micr. Soc., 1888 (7) Fr. Leydig, "Ueberden Ran und die systematise Stellungderltaderthiere " Z-it.f. v. Zool.,vi., 1854. (8) Mi. H. Gossc, Phil. Trant., 1866. '(9) F. Cohn, Zeit /. if. Zool,, vii., Ix, and xli. (10) Ph. H. Gosse, Phil. Trant., 1858. (11) Pritchard lnfu$oria, 1861. (IS, 18. 14) C. T. Hudson, "On Pedalion," Quart. Jour. Micr Sci., 1872, and Monthly Mirr.Joiir.. 1S71 and 1872. (15) E. Ray Lankester "On Pedalion," Quart. Jour. Micr. Sci., 1872. (16) El. Mecznikow, " On Aptiliu lenti- formit?' Zeit. f. tc. Zool., 1872. (17) C. Semper, "On Trochosphtera," Zeit. f. v. Zool., xxii. is;.'. (18) K. Eckstein, " Die Kotutoriender UniKi-m'iiil <m (iic sscn, " Zeit.f.tr. Zool., 1883. (19) C. T. Hudson, "On an Attempt to uvla-^iiN lioilfers," Quart. Jour. Micr. Sci., 1884, (A. G. B.) ROTROU,- JEAN DE (1609-1650), the greatest tragic poet of France before Corneille, was born on August 21, 1609 at Dreux in Normandy, and died of the plague at the same place on the 28th June 1650. His family was of small means but of not inconsiderable station, uinl seems to have had a kind of hereditary connexion with the magistracy of the town of Dreux. He himself was " lieutenant particulier et civil, " a post not easy to trans- late, but apparently possessing some affinity to a Scotch sheriffship substitute. Rotrou, however, went very early to Paris, and, though three years younger than Corneille, with whom he was intimately acquainted, began play-writing before him. With few exceptions the only events recorded of his life are the successive appearances of his plays and his enrolment in the band of five poets who had the not very honourable or congenial duty of turning Richelieu's dramatic ideas into shape. Rotrou's own first piece, L'Ifypocondriaq'ue,. appeared when he was only seventeen. His second, La Bague de I'Oubli, an adaptation in part from Lope de Vega, was much better, much more sugges- tive, and much more characteristic. It is the first of several plays in which Rotrou, following or striking out for himself a way which did not lead to much for the time but which was again entered at the Romantic revival, endeavoured to naturalize in France the romantic comedy which had flourished in Spain and England instead of the classical tragedy of Seneca and the classical comedy of Terence.' Corneille, as is known to readers of his early work, had considerable leanings in the same direction, and yielded but slowly and unwillingly to the pressure of critical opinion and the public taste. Rotrou's brilliant but hasty and unequal work showed throughout marks of a stronger adhesion to the Spanish (it is needless to say that neither writer is likely to have known the English) model. Cleagenor et Doristee, Diane, Les Occasions Per- dues, L'Heureuse Constance, pieces which succeeded each other very rapidly, were all in the Spanish style. Then the author changed his school, and, in 1632, imitated very closely the Menaechmi of Plautus and the Hercules (Et&iis of Seneca. A crowd of comedies and tragi-comedies followed, and by the time he was twenty-eight (when documents exist showing the sale of two batches of them to the bookseller Quinet for the sum of 220 livres tour- nois) Rotrou had written nearly a score of plays. He was married in 1640, and had three children, a son and two daughters (none of whom, however, continued the name), and it seems that he went to live at Dreux. Pre- viously, vague and anecdotic tradition describes him as having led rather a wild life in Paris, and especially as having been much addicted to gambling. Among his pieces written before his marriage were a translation of the Amphitryon under the title of Les Deux Sosies, which was not useless to Moliere, Antiffone, which was not useless to Racine, and Laure Persecutee (in the opposite style to these classical pieces), which has much merit. These were followed by others until, in 1646 and 1647, Rotrou pro- duced his three masterpieces, Saint Genest, a story of Christian martyrdom containing some amusing by-play, one noble speech, and a good deal of dignified action ; Don Bertrand de Cabrere, a comedy of merit ; and Ven- ceslas, which is considered in France his masterpiece, and which in a manner kept the stage till our own times. The subject (in which a father, being constrained to choose between his duty as king and his parental affection, pardons his son for a murder he has committed, but immediately abdicates as feeling himself unworthy to reign) was taken from Francisco de Rojas ; the execution,
