1905.] ANATOMY OF LIMICOLIXE BIRDS. 167 



muscles are present, and, save that in Hydropliasiamis 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-fiexorius, Ischio-Jlexorius, 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 groujied these divergences round four central types. The 

 conditions in the Limicolas 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 

 {P'ub-isckio-femoralis internus) sends a strong slip to the middle 

 head (internal femoral) of the gastrocnemius, or may be actually 

 fused with it. The intei-nal femoral head of the gastrocnemius 

 at its insertion to the femur is parallel with and distad of the 

 accessoiy or femoral attachment of the caud-ilio-fiexorius ; in 

 VcmeUus and Himantopus the edges of the two are in close contact, 

 although they are not actually fused as in the RalKdse. In all 

 the other birds on my list they are quite as in Otis. From the 

 I'aphe between the accessory and main portion of the caud-ilio- 

 fiexorius 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-fiexorius. 



Gastrocnemius, external femoral head. — Tliis is double in 

 Vanellus, Himantopus, and C'haradrius, 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 Eurypyga, and 

 the enormous undivided head in Heliornis. I have not in- 

 formation as to the occurrence of a similar variation of the external 

 head of the gastrocnemius in other groups. 



Ilio-fihidaris (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 Grui- 

 formes generally in all the birds on my list. The fleshy origin 

 is unusualty large. 



Puh-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 digitorum commtcnis. — This has the normal arrange- 

 ment and relations in all. Its tendon of insertion breaks up into 

 two central slips for digit 3 and a single lateral slip at each 



