COB^A. 



[ 151 ] 



COCCONEIS. 



The proper identification of vegetable 

 structures in coal must of course depend 

 upon a sufficient knowledge of the characters 

 of vegetable tissues and organisms being 

 possessed by the observer. 



BiBL. Witham, Internal Structure of 

 Fossil Vegetables, Fidinh. 1833; Link, Ueb. 

 den Ursprung der Steinkohlen, ^'C, Abhandl. 

 Berlin Akadem. 1838. p. 34 ; Goppert, 

 Preisschrift ueber Steinkohlen, Leiden, 1848; 

 Lindley and Hutton, Fossil Flora; Schleiden 

 and Schmidt, Geognost. Verh'dltn. des Saal- 

 thales, Leipzig, 1846; Ehrenberg and Schulz, 

 Ber. Berlin Acad. Oct. 1844, Annals Nat. 

 Hist. xvi. p. 69 ; Bailey on Anthracite Coal, 

 Ann. Nat. Hist, xviii. p. 67 ; Unger, Genera 

 et Species Plant. Foss. 1850. 



COB^A, Cuv.— A cHmbing Dicotyledo- 

 nous plant, of the Nat. Order Polemoniacese, 

 common in cultivation, remarkable for the 

 curious pyriform cells upon its seeds, con- 

 taining a spiral fibre (PI. 21. fig. 20). See 

 Spiral Structures. 



COCCIDIUM.— A form of fructification 

 in the FLORiDEiE. 



COCCINELLA, Linn. (Lady-bird). A 

 genus of Insects, of the order Coleoptera, and 

 family Coccinellidae. 



C. septempunctata, the common lady-bird. 

 This insect exhibits the cu'culation through 

 the elytra. If one of these is separated 

 from the body without being detached, and 

 arranged in such manner that it may be 

 viewed as a transparent object, slow and 

 uniform continuous currents, one ascending 

 and the other descending, willbe seen between 

 the laminae of which the elytrum consists. 

 On dinding the latter, an amber transparent 

 liquid containing colourless globules escapes. 



BiBL. Nicolet, Ann. d. Sc. nat. 3rd ser. 

 7 ? ; Westwood, Introduction, 4*c. ; Curtis, 

 Brit. Ent. 208 ; Stephens, Illustr. Brit. 

 Entom. ; Herrich-Schaeff'er, Synops. gen. 

 Coccinell., Deutschl. Ins. hft. 128. 



COCCOCARPE.E. See Cryptonemi- 



ACEjE 



COCCOCHLORIS, Sprengel {Palmo- 

 glcBa, Kiitz.). — A genus of Palmellacese 

 (Confervoid Algae), consisting of green mi- 

 croscopic cells, oval or globular, imbedded 

 in a gelatinous matrix, which is at first 

 definite in form(thus differing from Palmella), 

 and subsequently effused and shapeless. The 

 green cells are vesicles, filled with granular 

 colouring matter (chlorophyll) when in active 

 vegetation. They multiply by division, and 

 besides this, some of them grow much larger 

 than the rest, and have their contents con- 



verted into a number of cells ; these large 

 cells become free from the general frond and 

 lay the foundation of a new^ one, originally 

 of definite form, w hich increases in size by 

 the division of the individuals within a per- 

 sistent gelatinous investment. Brebisson, 

 Ralfs and Al. Braun describe a process of 

 conjugation in C. Brebissonii. Two ordinary 

 cells come into contact, and their membranes 

 become fused ; the intermingled contents 

 then undergo a metamorphosis, brownish 

 oil-globules replacing the chloro])hyll, and 

 the ' spore-cell ' thus produced passes through 

 a period of rest before resuming its vegeta- 

 tive development. Ralfs states that the 

 slender filamentous bodies sometimes found 

 in the frond are part of the organization of 

 the plant. We think there must be some 

 error here (see Palmellacese). Several 

 British species are described : 



1. C. j9rofM6er«w5, Spreng. Frond green, 

 irregularly lobed, spreading on the ground, 

 cells elliptical, about 1-3000", enlarged vesi- 

 cles 1-500 to 1-1000". Hassall, Br. Fr. 

 Alga, pi. 76. fig. 7, pi. 82. figs. 6-10; Pal- 

 mella protuberans, Grev. Sc. Crypt. Fl. 

 pi. 243. fig. 1. 



2. C. muscicola, Meneghini. Hassall, I. c. 

 pi. 78. figs. 3 a, 3 b. 



3. C. hyalina, Menegh. Aquatic. Hass. 

 /. c. pi. 78. figs. 2 a, 2 b. 



4. C. depressa, Menegh. Hass. I. c. pi. 7S. 

 4 a, 4 b. 



5. C. Mooreana. Hass. /. c. pi. 78. la, lb. 



6. C. rivularis. Hass. I, c. pi. 78. 6 a, b. 



7. C Grevillei, Hass. Frond minute, 

 densely crowded, globose or somewhat lobed, 

 green. In heathy moist situations, frequent. 

 Hass. I. c. pi. 78. figs. 7 (i,b and 8 ; Palmella 

 botryoides, Grev. Sc. Crypt. Fl. pi. 243. 

 fig. 2. 



The plants are not yet satisfactorily under- 

 stood ; the relations to Palmella and Glceo- 

 capsa are confused. 



BiBL. As above; also Meneghini, ilfo/?o^r. 

 Nostochinearum ; Kiitzing, Phyc. generalis; 

 Al. Braun, Rejuvenescence, c^c, Ray Soc. 

 Vol. 1853 (as Pahnoglcea) ; Ralfs, Ann. Nat. 

 Hist. ser. 2. vol. ii. p. 312 (as Palmella)', 

 Nageli, Einzell. Algen. Zurich, 1849. 



COCCONEIS, Ehr.— A genus of Diato- 

 maceae. 



Char. Frustules single, depressed, adnate ; 

 valves elliptical, one of them with a median 

 line and central nodule. 



The valves are mostly covered with dots 

 (minute depressions), appearing like lines 

 under a low power. 



