MED- 
“oe the pith and the pericycle 
Zz. 
medullary sheath,—a ring of pro- 
toxylems a the pith of certain 
stems (40 a layer of white 
eri surrounding 
the axis meow of a medullated 
_netvestibre 
ated (med iila’té d) is 
eae gens Racaarstuscags ‘with a 
medu month ie 
isteuttated —the fibres 
of the whine: part of he brain and 
spinal cord, consisting of an axis- 
sheath, is in turn covere 
delica se the neuri 
oe — 
medusa (médi’s%) 7 Gk. 
one who rules. ] A jelly- ash ool 4 
Medousa, Medusa ty, 
shape.] Like a sehen or Pa ‘fish, 
medusoid (médi’soid) ~. Gk. 
Medousa, edusa; ezdos, like.] 
medusa - like free - swi . 
gonophore of Hydrozoa (zoo/.) ; 
like a jelly-fish or i sha ool, % 
medusom médi’s6m) 
Medousa, Medusa; soma, body.] 
A name given edusoid 
stage in the life-history of Obelia 
megagamete (még’ ——— nm. ([Gk. 
tes, a spouse. ] 
megagametocyt 
nm. [Gk. megas, large 
kytos, 
ma i and 
itself giving rise toa megagamete, 
frequently requiring piegermebesees 
to another host before its develo 
ment can proceed (zao/.). 
(még’Akar'iésit) 7. 
me 
[Gk. megas, large; aryon, nut; 
kytos, hollo A giant-cell of 
marrow with on rge annular 
lobulated nucleus, containing a 
number of nucleoli (avaz.). 
179 
MEG- 
megalaesthetes (még’dlés’théts) 7. 
lu. [Gk. megalon, — aistheti- 
kos, perceptive.] Sensory organs, 
sometimes in the Sot of eyes in 
megalon. 
large yinrobies t (ana 
még aloeonid"vim) 
[Gk. megalon, great ; 
offspri ng.] A large gonidium eat 
megalopa (még’ald’pa). Mega 
Pp op 
megalon, great; ops, 
ne i ng to the epulge stage 
t 
A pore in the 1 plates in 
ret = P santioen a megalaesthete 
n dire ommunication with the 
‘eeveiriot ae 2.). 
megalops (née sone nm. [Gk meg- 
ops, eye.] A larval 
ertain pe aceans, as 
crabs, conspicuous by large stalked 
eyes (zoo “*s 
ri ian alésfer’ ik) a. 
megalon, gre Sphaira, 
id 1 Of poiveiietasine F aimee: 
ifer shells, having a mega ry ae 
or large initial chamber (zoo/. 
megamere (m ena ig — megas, 
large ; mero. rt.] e of the 
large cells fernind yy ie shes primary. 
ait tgs of a developing ovum 
pb st aE — nm. [Gk. 
ucleus, kernel.) — 
e 
supporting as i as 
nonaclraeihRe (zo 
heric canbe Megalo- 
ot 
megasporangium (még’adsp6ran’jiiim) 
nm. [Gk. megas, large; _ 
seed; anggeton, vessel.] _A macro- 
Btn abt ager caer oe (bot). 
megaspore (m or) 7. ar 
megas, gre ore : * pores seed. | 
larger-sized spore of dimorphic 
forms in segimeciicile by spor 
formation (zoo/.) ; the larger snes 
