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ABRTJ'PT. (abruptus, Lai) Broken ; 

 craggy; steep; precipitous. In 

 botany, applied to leaves, when the 

 extremity of the leaf is, as it were, 

 cut off by a transverse line. 



ABBTJ'PTLY PIN'NATE. Applied to 

 pinnate leaves, terminated neither 

 with a leaflet nor a tendril. 



ABSO'BBENT. (from absorleo, Lat.) 



1. Any substance possessing the 

 property of absorbing, or sucking 

 up, fluids, or neutralizing acids; 

 as the earths, alumina, magnesia, 

 &c. 



2. In anatomy, the absorbents are 

 small pellucid tubes, which have 

 been discovered in most parts ef 

 the body, and are supposed to exist 

 in all. The absorbents begin by 

 numberless open mouths, too mi- 

 nute to be visible to the naked eye; 

 by the assistance, however, of 

 glasses, the orifices of the lacteals 

 have been seen in the human body, 

 and those of the lymphatics in 

 certain fishes. 



ABSO'BBENT SYSTEM. This consists of 

 the absorbent vessels and conglo- 

 bate glands; the former are divided 

 into lymphatics and lacteals, and 

 the thoracic duct, or common 

 trunk, in which they terminate. 



ACA'LEPHA. (a/ca\^0iy, a nettle, Gr.) 

 A class of zoophytes found swim- 

 ing in the waters of the ocean. 

 The acalephse are divided in to orders, 

 namely, the A. simplicia, and A. 

 hydrostatica. The latter, or hy- 

 drostatica, are recognized by one 

 or more bladders commonly filled 

 with air, by the aid of which they 

 suspend themselves in their watery 

 element. "In all parts of the 

 ocean," says Professor Grant, " are 

 numerous gelatinous animals, for 

 the most part of a simple and 

 transparent texture, such as the 

 Hedusa and Portuguese man-of- 

 war, and numerous other genera. 

 For the most part, those soft gela- 

 tinous animals (which are entirely 

 aquatic, and all of them marine) 

 possess a property by which they 



excite inflammation, when they 

 touch the surface of the skin, like 

 nettles. The Acalephae scarcely 

 possess a trace of a nervous system, 

 and are all aquatic. They float, 

 for the most part, by the action of 

 their own muscular power, or by 

 air-sacs, or by cilia. They feed 

 upon animals of extreme minute- 

 ness for the most part, on the 

 microscopic crustaceous animals, 

 which abound in the ocean as in 

 other waters." Cuvier places the 

 Acalephse in the third class of the 

 fourth great division of the animal 

 kingdom, or Radiata. Linnaeus 

 placed them in the class Zoophyta, 

 order Gelatinous zoophytes. See 

 Malactinia. 



ACAI/T'CTNOTJS. A term applied to 

 plants which want a calyx. 



ACA'MAS, A genus of fossil multilo- 

 cular, straight and conical shells ; 

 mouth round and horizontal; si- 

 phuncle central; summit pierced 

 by eight small tuberculated aper- 

 tures, disposed round a stelliform 

 figure ; the septa conical, plaited at 

 the bottom, and plain at the edge. 

 The substance spathose, similar to 

 that of belemnites. Parkinson. 



ACANA'CEOTJS. (from a/cai/o?, Gr.) 

 Armed with spines or prickles. 



ACA'NTH. The acanths constitute a 

 family of ichthyolites, of the Old 

 Bed Sandstone, rich in genera and 

 species, forming an intermediate 

 link between the placoids and the 

 ganoids. 



ACA'NTHA. (axavOa, Gr.) 



1 . In botany, the spine or prickle 

 of a plant. 



2. In zoology, a term for the 

 prickly fins of fishes. 



3. In anatomy, the spinous pro- 

 cess of a vertebra. 



ACANTHA'CEOITS. (acanthace, !Fr.) 

 Possessing spines or prickles. 



ACAN'THODES. The name assigned 

 to a genus of ichthyolites of the 

 old red sandstone, characterised 

 by having a spine or thorn on 

 each fin. 



