2 GLOSSARY. 



Acanthoc'phala (Gr. akantha, a thorn ; kephale, the head). 



A group of parasitic Invertebrata having a number of 

 recurved hooks on the proboscis. 

 Acantho didae (Gr. akantlwdes, thorny). A sub-order of Ganoid 



fishes. 

 Acanthd'pteri (Gr. akantha, a thorn; ptcron, a wing or fin). 



A group of Teleostean fishes having spiny fins. 

 Acari'na (Gr. akdri, a. mite). A group of Arthropods which 



includes the mites and ticks. 

 Accesso'rius ad flio-costalem (L. accessory to the ilio-costah's). 



One of the dorsal muscles of the trunk. 

 Acci'pitres (L. acclplter, a hawk). In the old classification of 



birds, the order which included the birds of prey. 

 Acephalous (Gr. a, without; kephale, the head). Without a 



distinct head. 

 Acer vulus cgr'gbri (L. acervulus, a little heap ; cerebrum, the 



brain). A mass of gritty matter contained in the pineal 



gland. 

 Aceta bulum (L. a vessel for holding vinegar). The cavity in 



the innominate bone into which the femur articulates. Also 



applied to the suckers 'with which the cephalic processes of 



some Cephalopoda are provided. 

 Ach6 tidae (Gr. achetes, a grasshopper). The crickets. 

 Achla'mydate (Gr. a, not ; ehlamys, chlamydos, a cloak, mantle)- 



A term applied to those Branchiogasteropods which 



are destitute of a mantle. 

 Aciculum (L. diminutive of dcus, a needle). A sharp pointed 



process carried by the parapodiaof the polychoete Annelida. 

 Acine'tae (Gr. akinetos, immoveable). A group of the Infusoria, 



the members of which -in the adult stage are non-locomo- 

 tive. 

 Acine'tifonn. A term applied to the embryo Infusorians, which 



resemble the Acineta. 

 A'clni (L. drfnus, a grape). The small granulations composing 



the substance of some glands. 

 Acotyle'donous (Gr. a, not ; kotyledon, a cup-shaped hollow). 



Applied to cryptogamic plants whose spores have no 



cotyledons or seed-leaves. 

 Acri'didae (Gr. akris, akridos, a grasshopper) . The grasshopper 



tribe of insects. 

 A'crodont (Gr. akron, the summit ; odous, odontos, a tooth). 



Having the teeth attached by their bases to the summit 



of the parapet of the jaw, as in some of the Lacertilia. 



