7 Crust, 
CRUSTACEA, 
there are no cones, no rods, and no facets in the eye of LimuluSy but a 
series of solid, chitinous, conical bodies, resembling Minie-rifle balls, 
their ends free, projecting into the interior of the body and enveloped by 
black pigment; these are the “ conical lenses” of Grenadier. Am. Nat. 
xiv. pp. 212, 213, & 503-508; Ann. N. li. (5) v. p. 435; J. R. Micr. iii. 
pp. 947 & 948. 
S. F. Smith states that two apparently cornea-like areas are to be 
found on the ophthalmic lobe of Polycheles sculptus^ but he was not able 
to detect any evidence of facets ; the green gland opens into a tubular 
process on the oral side of the proximal segment of the antenna. Ann. 
N. H. (5) V. pp. 269-273. 
The hollow “ phymacerite ” or osseous tubercle on the first joint of the 
antennae in the Decapoda, the opening of which is closed by a thin mem- 
brane, is probably an organ for hearing ; C. S. Bate, Rep. Brit. Ass. 
1880, pp. 239 & 240. 
JOURDAIN describes the sensory rods in the inner antennae of the 
Crustacea {Decapoda and Ampliipoda). C. R. xci. pp. 1091-1093 ; abstract 
in J., R. Micr. Soc. (2) i. p. 241. 
Bellonci has found olfactory glomerules in the brain oiNepliropv. nor- 
wegicus^ and thinks that the external appendage of the antennulae is the 
olfactory organ ; Mem. Acc. Bologn. (4) i. pp. 429 & 430. 
3 . Circulation and Respiration, 
The physiology of the heart in the Decapoda is the subject of a paper 
by F. Plateau, Arch. Biol. i. pp. 595-695, 2 pis. (not seen by the 
Recorder). Abstract in J. R. Micr. Soc. (2) i. p. 41. 
C. Claus has examined the vascular system in the larvae of Squilla 
{Alima) and states that it is more developed than hitherto known for the 
Stomapoda generally ; the vas dorsale has a distinct enlargement in front 
corresponding to the heart of the Decapods, it is provided with a pair of 
large openings and sends a median cephalic aorta to the eyes and a pair of 
lateral arteries to the brain, and feelers, &c. ; the rest of the vas dorsale 
has twelve pairs of clefts, and sends off thirteen pairs of lateral arteries 
and a single hinder aorta ; the existence of a median ventral aorta is 
stated, it has its origin from the left or right cardiac artery ; the author 
also states the presence of a sympathetic nerve on. the dorsal side of the 
vas dorsale. Zool. Anz. iii. pp. 611-617. 
Incidental observations upon the pulsations of the heart in the crayfish 
and in Eriphia spinifrons are made by Krukenberg in Yergleichend- 
physiologische Studien, iii. pp. 164, 167, & 168. The number of 
the pulsations in one minute is very variable, 20-100 ; if the heart is cut 
across, the movements continue in the hinder part, but they cease instan- 
taneously if this hinder part is cut longitudinally into two symmetrical 
parts; atropine renders the pulsations slower, veratrine causes a diastolic 
paralysis of the heart, but the pulsations recommence on the application 
of digitaline. 
E. VON Beneden states that he observed in 1868, and published in 
1873, the peculiar system of closed vessels with red blood without 
