D. H. DE Souza 
497 
should be noted that all the equations give fairly good values for the male Egyptian 
pelvis III and most of them for the male English pelvis V. 
The best of the formulae obtained from the measurements of the American 
Indian female pelvis for finding the obstetric conjugate are therefore applicable 
to the modern European female pelvis, and will give good results even for the 
male pelvis. 
(B) Transverse diameter {brim). The inter-cristal ("61), inter-spinous ( - 52), 
and antero-posterior ("35), are the diameters most closely correlated with the 
transverse diameter. By taking them singly and combined, equations for finding 
this diameter were formed. Equations were also formed from the height of the 
hip bone taken singly or combined with the diameters. This bone measurement 
has proved serviceable in finding the obstetric conjugate and was used here, as its 
correlation with the transverse diameter also is fairly high (right -48, left - 45). 
equations 1 
vere obtained : 
(A;) 
T = 
•305 A" + 5 096 ± -386. 
(0 
T = 
■2288 + 7-791 + -415. 
(m) 
T = 
•284^ + 9-673 + -455. 
(n) 
T = 
•261 K + -0495 + 4 864 ± -385. 
(o) 
T = 
•221 K + -061 £ + 4604 + 4-044 ± -374. 
(P) 
T = 
■341 R + 6-398 ± -427. 
(q) 
T = 
•320Z + 6794 + -433. 
(r) 
T = 
•248 A" + •] 44 A + 3-799 ± -378. 
(s) 
T = 
•259 A + 115 A + 4-078 ± -381. 
(t) 
T = 
•169S + -221A + 4-S83 ±-392. 
(«) 
T = 
•174S + -192Z + 5-323 + '398. 
(V) 
T = 
202 AT + -050 # + -145.R + 3-835 + -376. 
(w) 
T = 
•217A'+-047S + -113Z + 4-155 ± -380. 
Of the equations formed by taking the measurements singly, namely (k) from 
inter-cristal, (I) inter-spinous, (m) antero-posterior diameter, (p) height of right 
hip bone, (q) height of left hip bone, (k) has the lowest probable error, "386. This 
is slightly improved (-385) by combining the inter-spinous with the inter-cristal 
diameter as at (n). The inter-cristal diameter combined with the height of the 
hip bone gives a still lower probable error (right "378, left '381), as is seen in 
equations (r) and (s), while (t) and («) show that the inter-spinous diameter and 
the height of the hip bone together give a higher probable error even than the 
inter-cristal diameter alone (k). By combining three measurements, however, 
there is noticeable improvement. Equation (v) formed from the inter-cristal and 
inter-spinous diameters and the height of the right hip bone has a probable error 
•376 which is slightly lower than that of (r), from the inter-cristal diameter and 
height of right hip bone (-378); and (w), from the inter-cristal and inter-spinous 
