SEPIA-SESIA. 



647 



SEPIA (Linnaeus). A naked mollusc, universally 

 well known by the familiar name of the cuttle-fish, 

 and the dried calcareous internal support is used as a 

 dentifrice. They are abundantly found in all climates, 

 and many of them attain a considerable size. Under 

 the article CEPHALAPHORA, this genus is more amply 

 described. 



SEPIDIUM (Fabricius). An extensive genus 

 of coleopterous insects, belonging to the family Pime- 

 IM<z, having the antenna filiform, the fourth and fol- 

 lowing joints being obconical, the thorax depressed, 

 with the lateral margins dilated, and with a dorsal 

 channel. The species are destitute of wings, and are 

 found in sandy and uncultivated districts, in the 

 warmer parts of the old world ; several species are 

 found in the south of Europe. They are of a mode- 

 rate size and black colour. 



SEPIOLA (Leach). A species of naked mollusc 

 of the eenns Loligo. 



SEPIOTENTHIS (Noblet). A species of naked 

 mollusc of the genus Loligo. 



SEPSIS (Fallen). A genus of small dipterous in- 

 sects, belonging to the family Muscid<z, having the body 

 of a moderately elongated form ; the legs long and 

 slender ; head globular, antennal joints small, with the 

 terminal seta naked ; palpi filiform. These are active 

 little flies, generally of a shining black or bronzed 

 colour, which are to be observed in summer upon 

 various flowers and leaves in the sunshine, where 

 they appear to delight in keeping their wings in a 

 constant but moderately slow vibration. Some of 

 the species exhibit various remarkable variations in 

 the structure of the legs and some other parts in the 

 opposite sexes. The type is the Musca vibrans of 

 Linmens. 



SEPTARIA (Lamarck ; SKRPULA POLYTHALA- 

 MIA, Linna?us). A very long testaceous tube gra- 

 dually attenuated to its upper end, and interiorly 

 divided by vaulted separations, seldom complete, the 

 extremity of which is terminated by two slender 

 tubes without any interior partitions. This sheath, 

 no doubt, incloses a bivalve shell at its end, but we 

 have never seen a perfect specimen. 



SEPTAS (Linnaeus). A remarkable genus, in so 

 far as it is the only individual genus which constituted 

 the fourth order of the seventh class of Linnaean 

 botany. Every member of the flower has seven 

 divisions. Jussieu has placed it among the Sem- 

 pervivacece. 



SERAPIAS (Linnaeus). A genus of south Eu- 

 ropean herbs, belonging to Orchideae. Like others 

 of the order, the flowers are curious, and the species 

 are so hardy, that they bear our winters with but a 

 little covering. 



SERICA (MacLeay). A genus of coleopterous 

 insects, belonging to the family Melolonlhldce, having 

 the antennae nine-jointed ; the body ovoid, as though 

 inflated, and often silky or exhibiting various change- 

 able reflections of colour ; all the tarsal claws are 

 bifid, and the thorax is much broader than long. 

 These insects are of small or but moderate size ; they 

 reside in the perfect state amongst vegetables, of 

 which they devour the leaves, the larvse probably 

 feeding upon the roots like those of the Mdolonthcc. 

 The type of the genus is the common English Serica 

 brumiea. 



SEROLIS (Fabricius). A remarkable genus of 

 crustaceous insects, belonging to the order Isopoda, 

 and family Cymothoidce, having the body depressed 



and nearly circular, composed of transverse segments, 

 four of which constitute the abdomen ; the head is 

 large, with the eyes placed upon tubercles, and situ- 

 ated upon the summit of the head. This genus is 

 composed of two or three species of Crustacea, inha- 

 biting the southern extremity of South America, and 

 in the form very nearly approaching to the extinct 

 tribes of Trilobites (which see). The type of the genus 

 is the Cylaothoa paradoxa of Fabricius. 



SERPENTINE. Under this name are placed some 

 of the most picturesque rocks which ornament and 

 protect the British shores. Serpentine derives its 

 name from the variety of tints which it exhibits, 

 varying from a bright red to a vivid green. Some 

 of the varieties admit of a fine polish when employed 

 for ornamental purposes. Serpentine is seen in its 

 highest beauty on the coast of Cornwall, where it 

 forms the greater part of the Lizard promontory, and 

 presents a series of natural arches and columns. At 

 Portsoy in Banffshire it is associated with granite, and 

 in other cases it is incumbent on beds of porphyry. 



SERRATULA(Linnaeus). A genus of herbaceous 

 annual, biennial, and perennial plants, mostly natives 

 of Europe. They belong to Composites. Their En- 

 glish name is sawwort, and one of them, the S. tinc- 

 toria, is useful to dyers. 



SERRURIA (Dr. R. Brown). A fine genus of 

 evergreen shrubs from the Cape of Good Hope, and 

 allied to Protea, and of course belongs to the same 

 order ; they also require similar treatment, and are 

 well worth a place in every collection. 



SESAMEJ3. A natural order containing four 

 genera, viz., Tourettia, Martynia, Craniolaria, and 

 Sesamum. Of these genera there are eight species. 

 The flowers are didynamous, and the plants are in- 

 nocuous, and are used for both food and medicine. 

 They are chiefly remarkable for the abundance of 

 bland oil contained in their seed, which is as sweet 

 as that of olives, and is expressed in the Levant and 

 other eastern countries for domestic use. 



SESBANA (Persoon). A genus of tropical plants 

 mostly annuals, two of them are shrubs, one of which 

 was called JEschynomene by Linnaeus. They belong 

 to Leguminosce. The species are potted in sandy 

 heath mould, and require the hottest part of the 

 stove. 



SESELI (Linnaeus). A genus of annual, biennial, 

 and perennial herbs, chiefly natives of Europe. They 

 belong to Umbellifera; ; none are in cultivation. 



SESIA (Fabricius). A genus of lepidopterous 

 insects, belonging to the family Sphingidee, having the 

 wings horizontal, somewhat unclosed when at rest, 

 and always more or less hyaline, and denuded of 

 scales ; the tongue is long and spirally rolled up 

 when unemployed ; the antennae serrated in the 

 males, and simple in the females, with a small bundle 

 of scales. These curious insects have more the ap- 

 pearance of bees and wasps than lepidopterous insects ; 

 the abdomen is very thick and hairy, being terminated 

 by a fan of scales. The caterpillars resemble those 

 of the typical Sphingidae, having the body long and 

 furnished with a dorsal curved horn near its extre- 

 mity. They feed upon the leaves of various plants, 

 and undergo their transformations under ground. 

 The perfect insects fly with great agility, frequenting 

 exposed situations in woods where various low spring- 

 flowers are in blossom. There are two British spe- 

 cies ; Sphinx bombyliformis (the narrow bordered bee 

 hawkmoth) and S.fuciformis (the broad bordered bee 



