GLOSSARY. 



Ab-do'men (Lat. abdo, I conceal). The posterior cavity of the hody, contain- 

 ing the intestines and others of the viscera. In many Invertebrates there is 

 no separation of the body-cavity into thorax and abdomen, and it is only in 

 the higher Ammiom that a distinct abdomen can be said to exist. 



Ab-ee'raht (Lat. aberro, I wander away). Departing from the regular type. 



Ab-nob'mal (Lat. ab, from ; norma, a rule). Irregi3ar ; deviating from the 

 ordinary standard. 



Ab-o-ma'sdm. The fomth cavity of the complex stomach of the Euminants. 



A.-BBiifOH'i-ATE (Gr. a, without ; iragoMa, gills). Destitute of gills or bran- 

 ohise. 



A-oa-lb'ph^ (Gr. ahaUpTis, a nettle). Applied formerly to the Jelly-fisbes or 

 Sea-nettles, and other Eadiate animals, in consequence of their power of 

 stinging, derived from the presence of microscopic cells, called " thread- 

 cells," in the integument. 



A-oas-tho-oeph'a-ia (Gr. akantha, a thorn ; JeephaU, head). A class of para- 

 sitic worms in which the head is armed with spines. 



A-OAif-THO-ME-TEi'ifA (Gr. akantM ; and Tnetra, the womb). A family .of i^o- 

 tozoa, characterized by having radiating siliceous spines. 



A-OAN-^HO-PTBE-Ta'-i-i (Gr. ahantha, spine ; pterwu, wing). A group of bony 

 fishes with spinous rays in the front part of the dorsal nn. 



A-oab'i-na ^Gr. akari, a mite). A division of the AracTmida, of which the 

 Cheese-mite is the type. 



Ao-oke'tion. 



A-oeph'a-lohs (Gr. a, without ; hephale, head). Not possessing a distinct 

 head. ' 



A-oe-tab'd-la (Lat. acetabulum, a cup). The suckers with which the cephalic 

 processes of many C^Mlopoda (Cuttle-fishes) are provided. 



A-oe-tab'u-lum. The cup-shaped socket of the hip-joint in Vertebrates. 



Ao'ei-ta (Gr. akritos, confused). A term sometimes employed as synony- 

 mous with R-otozoa or the lowest division of the animal iiingdom. 



Ao-ti-hom'bee3 (Gr. aletim, a ray ; Trteros, a part). The lobes which are 

 mapped out on the surface of the body of the GtenopTuira, by the cteno- 

 phores, or comb-like rows of cilia. 



Ao-tin-o-so'ma (Gr. aktin ; and soma, body), Employed to designate the 

 entire body of any Aclinozoon, whether this be simple (as in the Sea- 

 anemones), or composed of several zooids (as in most Corals). 



Ao-TiN-o-zo A (Gr. aktin; and zoon, an animal). That division of the Gcdrni- 

 terata of which the Sea-anemones may be taken as the type. 



Ad-el-ab-thbo-so'ma-ta (Gr. adelos, hidden; artkroa, joint; eoma, body). 

 An order of the Araohmda. 



Ad-etio'tob. 



A-e'bi-al. 



A-oam'io (Gr. o, without; gamoe, marriage). Applied to all forms of repro- 

 duction in which the sexes are not directly concerned. 



