GLOSSARY. 281 



Loculi. Certain spaces in the corallite of an Actinozoon between 



the vertical septa. 

 Lophophore. A ridge on which the tentacles are placed in the 



Polyzoa. 

 Lores. A stripe on each side between the bill and the eye in 



birds. 

 Lorica. A shield. In the Eotifers a cylindrical gelatinous shell, 



into which they can withdraw their bodies. 

 Lymphatic vessels or absorbents. Minute and delicate vessels 



which collect the products of digestion and detrita of nutrition 



and convey them into the venous circulation. The lacteals are 



the lymphatics of the small intestines. 



Madreporiform tubercle or madreporite. A wart-like body placed 

 externally on the aboral surface of starfishes. Its use is un- 

 known. 



Malacology. The study of the Mollusca. 



Malpighian tubes. Delicate vessels opening into the intestines in 

 most insects ; they vary from four to a hundred. 



Mandibles. The upper and outer pair of jaws in the Arthro- 

 poda ; they correspond to the lower jaw of the Vertebrata. 



Mantibrium. (1) The process in the middle of the anterior border 

 of the sternum in mammals and birds (also Pr&sternum). (2) 

 In the Hydrozoa the central tubular body attached to the bell 

 or umbrella, the other extremity bearing the mouth. 



Marsupium. The abdominal pouch in the Marsupial. See Pecten. 



Mastax. The muscular bulb comprising the biting- and grinding- 

 organs of a Eotifer. 



Materialism. The denial of " spiritual substances " (Johnson). 

 Scientific materialism affirms " that every effect has its cause, 

 and every cause its effect." It rejects miracles and all super- 

 natural processes. Moral or ethical materialism is based on 

 material enjoyment and the gratification of the senses, and it 

 has no place among naturalists and philosophers. (See Hist, 

 of Great, i. 36.) 



MaxillcB. The lower pair of jaws in the Arthropoda. The upper 

 jaw only in the Vertebrata. 



Maxillipedes or foot-jaws. The three posterior of the six pairs of 

 appendages of the mouth of a Crustacean ; the two following 

 pairs are the maxillae, the last the mandibles. See Siagonopoda. 



Meconidia. Peculiar sacs of the hydroid genus Gonothyrcea. 



