BY WILLTAM A. ITASWELL, M.A.,.B.Sc. 401 



Meckel, although he gives no name to it, in his " System der 

 vergleich. Anat." iii., p. 388, and in his Archiv fiir Anat. u. 

 Physiol, pp. 278 and 279." 'Not having been able to consult 

 the volumes referred to here, I am unable at present to check 

 Dr. G-adow's identification of the muscle which I have ventured 

 to name lumbricalis with a muscle mentioned by Meckel and 

 occurring " in many other birds, e. g. the Batifco.'' No mention 

 is made of such a muscle by Owen in his ' Memoir on the Apteryx,' 

 in his article " Aves " in Tod's Cyclopaedia, or in his ' Com- 

 parative Anatomy and Physiology of Vertebrates,' in all of which 

 frequent reference is made to Meckel's ' Y ergleichende Anatomic,' 

 nor by Selenka in the ' Vogel ' of Bronn's ' Thierreich ' in which 

 Meckel is also constantly quoted, nor by Alix in his ' Appareil 

 locomoteur des Oiseaux ; ' nor does Grarrod mention it in his 

 paper on the Ostrich, in whicb the flexors of the toes are minutely 

 described (Collected Papers, pp. 101-104). 



The muscle referred to, which, if it be not an equivalent of two 

 coalescent lumbricales, has no homologue in Mammals, arises from 

 the under surface of the tendon of the flexor profundus just 

 before it divides, and, becoming bifurcated, is inserted into the 

 sheath containing the flexor tendons of the second and third toes. 

 Against Dr. Gradow's statement that it occurs in many other 

 birds and therefore is not characteristic of the Pigeons, I have to 

 place the fact that it does not occur in any of the numerous birds 

 — swimmers, waders, parrots, kingfishers, cuckoos and others — 

 that I have examined for it, with the single excaption of the 

 rasorial birds in which it is well-developed. Thus though not, as 

 I once regarded it, peculiar to the Pigeons, this muscle is a 

 characteristic one and is probably of some taxonomic value. If 

 it should prove to be common and peculiar to the Columb?e and 

 the Easores, it would prove an interesting minor link between 

 these groups. 



We may then define the Columhidce myologically as birds with 

 an expanded tensor accessox'ius, with the posterior belly of the 



