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Show 1905.] ANATOMY OF LIMICOLINE BIRDS. 167 muscles are present, and, save that in Hydrophasianus and Himantopus the semitendinosus and its accessory or femoral head were very small, the conditions I did not find to differ from the generalised state found in Gruiform birds. Insertions of Caud-ilio-flexorius, Ischio-flexor ius, and middle or posterior femoral head of Gastrocnemius.-In a former communication to this Society (7) I described the differences that exist amongst Gruiform birds in this respect, and I grouped these divergences round four central types. The conditions in the Limicoke are more uniform, and may be explained by comparison with the figure of the Otis type (7, text-fig. 83, p. 651). In all the birds the internal adductor muscle (Pub-ischio-femoralis internus) sends a strong slip to the middle head (internal femoral) of the gastrocnemius, or may be actually fused with it. The internal femoral head of the gastrocnemius at its insertion to the femur is parallel with and distad of the accessory or femoral attachment of the caud-ilio-flexorius; in Vanellus and Himantopus the edges of the two are in close contact, although they are not actually fused as in the Rallidse. In all the other birds on my list they are quite as in Otis. From the raphe between the accessory and main portion of the caud-ilio-flexorius a strong fibrous band runs downwards fusing with the middle head of the gastrocnemius, whilst another band from the same point of origin runs across to be inserted into the tibia, under the tibial portion of the gastrocnemius, generally in association with the similar insertion of the ischio-flexorius. Gastrocnemius, external femoral head.-This is double in Vanellus, Himantopus, and Charadrius, single in all the others. The two heads unite before the muscle joins with the conjoined tibial and inner femoral portions. This recalls the similar doubling in Cariama, the three heads in Otis and Evrypyga, and the enormous undivided head in Heliornis. I have not information as to the occurrence of a similar variation of the external head of the gastrocnemius in other groups. Hio-fbularis (text-fig. 28, IL.FIB. (1) & (2)).-This muscle, with its sling and connections, exhibits practically identical conditions, and these not differing from the state in the Gruiformes generally in all the birds on my list. The fleshy origin is unusually large. Pub-ischio-femorales (adductors).-These are both present in all the birds on the list. As I have mentioned above, the internal adductor has usually a strong connection with the middle head of the gastrocnemius. It is wider than the external adductor and shows traces of tendinous degeneration. Tibialis anticus and Soleus.-These are present and normal in all the birds on the list, the tibialis anticus passing through a ligamentous ridge. Extensor ddgitorum communis.-This has the normal arrangement and relations in all. Its tendon of insertion breaks up into two central slips for digit 3 and a single lateral slip at each |