1<*> SUMMARY OF CURRENT RESEARCHES RELATING TO 



neuromere, however, this assignment must lie made tentatively, although 

 the major root of the trigeminal is attached to this neuromere. The 

 neuroblasts in the somatic motor column of this neuromere do not pro- 

 duce a nerve. The transient nerve seen in this region in chick embryos 

 may be the somatic motor nerve of this metamere which lias disappeared 

 phylogenetically. The myotome of the metamere, however, is innervated 

 by the nerve of a post-otic metamere, the abducens. 



The fifth and last pro-otic metamere includes the fifth neuromere 

 and the fourth somite which is partly sub-otic. To this position it 

 presumably owes the loss of its myotome. To the degeneration of the 

 myotome may be attributed the loss of the somatic motor nerve of this 

 metamere. No sympathetic primordium develops in this segment and 

 the somatic sensory components are also lost. But the proliferation of 

 the cells of the facialis nerve from this neuromere justifies the inference 

 that they once have been present in this nerve. The loss of the myotome 

 of this and of the following somite, a loss in all probability due to the 

 enlargement of nerve ganglia and sense organ in this region, tends to 

 show that the preservation of the myotomes of the first, second, and 

 third somites is due to their functional relation with the eye-ball. The 

 eye muscles are the last remnants of the lateral trunk musculature 

 anterior to the ear. 



Regenerative Capacity of Lizards.* — G. Billiard reports on the 

 recovery of a green lizard after it had been mauled by a cat. The tail, 

 reduced to a stump, regrew six centimetres in the following year. 

 But a lost hind leg, bitten across the femur, was not regenerated. The 

 digits of another damaged limb simply formed a scar. Billiard con- 

 cludes that the limbs are never regenerated, and he makes the suggestion 

 that statements to the contrary are due to a confusion between newts 

 and lizards ! It may be noted that in AVeismann's well-known discussion 

 of regeneration it is stated that lizards do not regrow their legs. 



Hermaphrodite Amphioxus.f — J. H. Orton reports that an herma- 

 phrodite specimen of Amphioxus lanceolatus was taken at Plymouth, 

 which closely resembled one taken by Goodrich at Naples. It had one 

 gonadial pouch filled with ova and the remaining pouches filled with 

 spermatozoa. The liver and intestine were abnormal, but no parasites 

 were identified in the tissues to account for the abnormalities. It is 

 improbable that there is any normal sex-change in Amphioxus. The 

 three hermaphrodite specimens which have now been recorded have been 

 very small. The hermaphroditism is probably comparable to that not 

 unknown in some fishes. 



Orton notes that the spawning of Amphioxus has been observed in 

 June, and that larva? have been obtained from captive specimens. It is 

 suggested that the club-shaped gland may secrete a substance which 

 attaches the larva to objects, and that this function may be correlated 

 with the asymmetry shown in the early development. 



* Bull. Soc. Zool. France, xxxix. (1914) pp. 327-9 (1 fig.), 

 t Journ. Marine Biol. Assoc, x. (1914) pp. 506-12.(5 figs.). 



