686 



SYSTEMATIC HISTORY OF THE IXFUSOEIA. 



The ovary is rolled up like a ball ; contractile vesicles exist in three, and 

 glands in two species; transverse bands (foiu' to ten) are visible in two 

 species, and probably a respirator}^ tube in S. jjectinata and S. tremula, a 

 ti'emulous gill being also present in the former. The principal nervous matter 

 is a knotty mass suiTounding the head of the oesophagus ; and in the middle 

 of it is a large, roundish, red eye. In S. pectinata three pair of gangha and 

 strong nerves are also said to be seen ; but this is doubtful. Abdominal fluid 

 of a reddish -yellow colour. (For remarks on the genus, see Hydatina, p. 677.) 



Synchjeta pectinata. — Short, conical, 

 with two styles and two crest-like horns 

 anteriorly. " Are these horns," asks 

 Ehrenberg, "respiratory tubes, as in 

 Pohjarthra, and in Anur(ea ?" The live- 

 liness and uniform transparency of this 

 animalcule render it difficult to distin- 

 guish its various organs. The styles 

 arise from the muscle of the oesophageal 

 head, and appear as if belonging to simple- 

 toothed jaws. Eye blue. Egg-yelk con- 

 taining heaps of red fat-globides. (xxxui. 

 422, a dorsal view showing its organiza- 

 tion.) Amongst Confervae. 1-120". 



S. Baltica. — Ovate ; rotary clusters 

 and styles, four each ; crest single, sessile. 

 This creature is supposed to occasion 

 phosphorescent light in the ocean. In 

 two samples of water received by Ehren- 

 berg at Berlin, from Kiel, the Imninous 



tion of light from this SynchcBta, as did 

 Baker a century ago. Ehrenberg thinks 

 it takes place only when developing ova. 

 1-100".^ . 



S. ohlonga. — Oblong, with six rotary 

 clusters, and four styles ; crest sessile and 



single. 



Distinguished from the follow- 



ing by the form of the pancreatic glands. 

 Amongst Coufervae in spring. Length 

 about 1-100". 



S. tremula ( VorticeUa tremula, M.). — 

 Body tridy conical, wdth six rotary clus- 

 ters, four styles ; crest none ; granules of 

 yelk dark coloured. Length about 1-160". 

 Mr. Gosse thinks this may be a dioecious 

 species. 



S. mordax (Gosse). — Body conical, 

 subventricose; toes minute; auricles large, 

 pendent j principal styles four, the larger 

 (or lateral) pair sometimes branched ; eye 



property existed; but this species, though | rather small, briUiant ; two pahs of pro- 

 present, did not evolve any light. Mi- j trusile snapping jaws. ' 1-72". 

 chaelis, however, has noticed the produc- | 



Genus SCARIDIUM (XXXUI. 423).— Eye cervical, single, flat, lenticular, 

 the compound rotary organ armed in front with an uncinus or hooked bristle ; 

 foot forked, very long, and adapted for leaping or sprmging — hence the name. 

 Oesophageal head oblique, with unequal, double -pointed (single) teeth to the 

 jaws ; oesophagus short, narrow, opening into a simple, wide, conical alimen- 

 tary canal ; supposed glands spherical, two. Posteriorly, above the intestine, 

 are a ball-like ovaiy and a contractile vesicle. The foot has two club-shaped 

 muscles ; and its apparent articulations are very remarkable. A central gan- 

 glion exists between the rotary lobes. Muscles with transverse strise. Shell 

 of the ovum (winter ovum ?) clothed at both ends with scattered hairs. 



ScAniDiUM longicaucla (Trichoda longi- 

 cauda, M.). — Foot twdce as long as the 

 body, toes half as long as the foot ; the 

 animal springs or leaps quickly, by a 

 rapid movement of the foot ; it does not 

 appear to have a lorica, and is distin- 

 guished from all other Rotatoria by the 

 length and bending-in of the foot, which, 

 as also the body, is covered with a stiff 



skin. Behind the eye is a transverse 

 fold in the neck, where the head di'aws 

 itself into the body ; the foot has also a 

 transverse fold when it bends, (xxxiii. 

 423, the animalcide extended, right side ; 

 fig. 424 the CESophageal head, with un- 

 equal jaws, &c., extended by pressure.) 

 Amongst Oscillatorise. Entire length of 

 thebodv 1-72"; without the foot, 1-216". 



Genus POLYARTHRA (XXXIII. 400-402 ; XXXVIII. 30).— Eye single, 

 cervical ; foot absent ; provided with cirri, or pectoral fins. The rotary organ 

 consists of four bundles of ciha, inserted in as many muscular sheaths ; they 

 sometimes appear like the double rotary organ of a Brachiomis. The form 

 of the body resembles Annrcca ; but it is soft, and the rotary organ double. 



