634 



SUPPLEMENT 



and rather bent upwards. 64. Trichoda delphinus. Ob- 

 long, fore part hairy, the tail turned back and trunca- 

 ted. 65. Trichoda clava. Similar to the preceding in 

 most respects. 66. Trichoda cuniculus. Oblong, tore- 

 part hairy, hind part rather acute, filled with molecules 

 and black vesicles. 67. Trichoda felis. Curved, large, 

 the fore part small, hinder part gradually diminishing 

 into a tail, under part set longitudinally with hairs. 

 68. Trichoda piscis. Oblong, fore-part hairy, hinder part 

 terminating in a very slender tail. 69. Trichoda larus. 

 Long, round, surrounded with hairs, the tail divided 

 into two points. 70. TricJioda lonyicauda. Cylindrical, 

 fore part truncated and surrounded with hairs, the tail 

 long, furnished with two bristles, and having two joints. 

 71. Trichoda fioca. Spherical, the circumference set 

 with hairs, and a small pedicle projecting from the body. 

 72. Trichoda inqui/inus. Sheathed in a cylindrical 

 transparent bag, having a little pedicle bent back within 

 the bag. 73. Trichoda inyenita. Sheathed, the bag de- 

 pressed, the base broadest. 74. Trichoda innata. Shea- 

 thed, in a cylindrical bag, with a pedicle passing 

 through, and projecting beyond it. 75. Trichoda trans- 

 fuga. Broad, fore part hairy, hinder part full of bris- 

 tles, one side sinuated, the other pointed. 76. Trichoda 

 ciliata. Ventricose, the hinder part covered with hair. 

 77. Trichoda bulla. Membranaceous, sides bent in- 

 wards, fore and hind parts furnished with hairs. 78. 

 Trichoda pellionella. Cylindrical, fore-part hairy, hinder 

 part furnished with bristles. 79. Trichoda cyllidium. 

 Egg-shaped, the apex gaping, the base hairy. 80. 

 Trichoda cursor. Oval, fore part hairy, hinder part fur- 

 nished with straight and curved hairs in two fascicles. 

 81. Trichoda pulex. Egg-shaped, with an incision in 

 the fore-part ; the front and base hairy. 82. Trichoda 

 lynceus. Nearly square, with a crooked beak, the 

 mouth hairy. 83. Trichoda erosa. Orbicular, fore-part 

 notched, one side furnished with hairs, the hinder part 

 with bristles. 84. Trichoda, rostrata. Depressed, muta- 

 ble, yellow, with long cilia, and feet tapering to a point. 

 85. Trichoda layena. Round, ventricose, with a long 

 neck, and the lower end set with bristles. 86. Trichoda 

 cftaron. Boat-shaped, with furrows, the fore and hind 

 parts hairy. 87. Triclwda ciinex. Oval, with a lucid 

 margin, front and hind part hairy. 88. Trichoda cicada. 

 Oval, with an obscure margin, fore part covered with 

 hairs on the under side, and the hinder part beardless. 



XIV. KERONA. An invisible worm with 

 horns. " Animalcules furnished with hooks 

 (uncini), bristles (setcs), or horn-like proces- 

 ses." 



Plate 35, fig. 58. Kerona pullaster. " The 

 fore part, in addition to the cilia, is stated to 

 have three setae. The cilia at the opposite 

 extremity are often separated ; at other times 

 they are collected in a cluster." 



KERONA SPECIES. 



1 . Kerona rostellum. Membranaceous, orbicular, with 

 one projecting point, the upper surface covered with 

 small horns. 2. Kerona lyncaster. Rather square, and 

 its disc furnished with shining horns. 3. Kerona histrio. 

 Oblong, membranaceous, with four or five black points 

 in the fore part, which are continually changing their 

 situation, thick set, with small globules in the middle, 

 among which four larger ones are perceived, probably 

 the eggs. 4. Kerona cypris. Egg-shaped, sinuated to- 

 wards the hind part, the fore part hairy. 5. Kerona 

 haustrum. Orbicular, with the horns in the middle, the 

 fore part membranaceous and hairy, and several bristles 

 in the hinder part. 6. Kerona haustellum. Differs 

 from the preceding only in wanting the bristles in 

 the hinder part. 7. Kerona patella. With a unival- 

 ved shell, orbicular, crystalline ; fore part somewhat 

 notched. 8. Kerona ranmis. Oval and rather flat, with 

 one edge bent, the opposite one ciliated ; the front fur- 

 nished with horns, and the hind part with bristles. 9. 

 Kerona pullaster. Described. 10. Kerona mytillus. 

 Rather clubbed, broad at both extremities, clear and 

 ciliated. 1 1 . Kerona Icpus. Egg-shaped, fore part hairy, 



the base furnished with bristles. 12. Kerona silurus. 

 Oblong^the fore and hind parts hairy, the back ciliated. 

 13. Kerona calvitium. Rather broad, oblong, with 

 glittering horns on the fore part. 14. Kerona pustulata. 

 Oval, convex, one edge of the hinder part sinuated, 

 both ends set with hairs, and several horns placed on 

 the fore part. 



XV. HJMANTOPUS. A pellucid, invisible, 

 cirrated* worm. 



Plate 35, fig. 58. Himanlopus larva. " This 

 is a very lively creature, swimming and turn- 

 ing in the water in a graceful and diverting 

 manner, inflecting itself, as shown in the 

 figure ; the body gradually decreases towards 

 the posterior, and at intervals several hairs 

 appear disposed along it. The margin is 

 fringed." 



HIMANTOPUS SPECIES. 



1. Himantopus acarus. Round and prominent, the 

 hinder part cirrated, the fore part sharp. 2. Himanto- 

 pus ludio. Curled, the upper part hairy, the tail ex- 

 tended upwards. 3. Himantopus sannio. Crooked, the 

 upper part ciliated, the under part hairy. 4. Himunto- 

 pus volutator. Lunated, the fore-part hairy. 5. Himan- 

 topus larva. Described. 6. Himantopus charon. Boat- 

 shaped, furrowed, the hollow part of the belly cirrated. 

 7. Himantopus corona. Semi-orbicular, flattened, 

 both sides cirrated. 



XVI. VORTICELLA. A small animal with a 

 vascular cup ; the mouth is ciliated, and ca- 

 pable of being contracted, the stem fixed. 



The variety that may be observed in these 

 minute animals confirms a principle, which, 

 the more it is inquired into, the more it will 

 be found to accord with the general operations 

 in nature, namely, that there is always a pre- 

 existent principle of life necessary to the orga- 

 nization both of animals and vegetables ; that 

 the alimentary and other particles which are 

 added to, or apparently belong to them, pro- 

 duce nothing of themselves; they are incapa- 

 ble of forming the least fibre, but they are able 

 to become constituent parts of one organical 

 whole, together with the instruments whereby 

 the former principle is manifested, and ren- 

 dered capable of acting upon certain orders of 

 creatures. The genus vorticella is very ex- 

 tensive. Miiller enumerates no less than se- 

 venty-five species, and other observers have 

 added to the number ; in this, however, and 

 in other similar instances, it would be better 

 if examination were conducted with a view to 

 lessen rather than increase the number of spe- 

 cies, that is to say, if the several stages of de- 

 velopment were carefully noted, when we be- 

 lieve many apparently distinct species would 

 be found to be one and the same, in its various 

 progressions towards maturity. The vorticella 

 differ considerably in their organization, and 

 Mr Pritchard has, in consequence, separated 

 them into two divisions, V. polycjastrica, and 

 V. rotatoria; the former of these includes the 



* That is, furnished with a tuft, or lock, of hair. 



