Primitive segments of the trunk, 342. 



spermatic cells, 374, 382. 



streak, 121, 133,135, 282 sec also 



Blastopore. 

 Primordial bone?, 615. 



bones, enumeration of, 619. 



cranium, 605. 



cranium, cartilaginous, 595, 607. 



cranium, chordal, 607. 



cranium, evertebral, 607. 



cranium, membranous, 595, 605. 



cranium, prechordal, 007. 



cranium, vertebral, 607. 

 Principles of development, 76. 

 Proamnion, 230. 



Processus ciliares, 479. 



pinealis, 432. 



styloideus of petrosal. 613. 



styloideus of radius and ulna, 644. 



vaginalis peritonei, 391, 396. 

 Prochorion, 224. 



Pronephric duct, 368, 359. 

 Pronephron, 353. 

 Pronucleus, 32. 



female, 32 sec also Egg-nucleus. 



male, 40 sec also .Sperm-nucleus. 

 Prostata, 402. 



Prostate gland, 402. 

 Protoplasmic radiation, 40, 51. 

 Protovertebrae, 162, 598 see also Pri- 

 mitive segments. 



Pterygoid process of sphenoid, 619. 

 Pubic bone, 639. 

 Pulmonary alveoli, 323. 



artery, 564. 

 Pupil, 478. 



Radiations of protoplasm, 40, 51. 



Radius, 64. 



Rathke's pocket, 285, 437. 



pouch, 285, 437. 



trabeculae cranii, 606. 

 Rauber's layer, 102. 

 Receptive elevation, 39. 

 Recessus labyrinthi, 493. 

 Regio olfactoria, 515. 



respiratoiia, 515. 

 Reichert's cartilage, 613. 

 Re-segmentation of vertebral column, 



598. 



Reserve material, 21. 

 Rete testis, 384. 

 Retina, 480. 

 Ribs, 6CO. 

 Ring-lobe, 442. 

 Roots of attachment of the chorion, 



260. 

 Round ligament, ?86. 



Rusconian anus, 88. 



digestive cavity, 83. 



S. 



Sacculus, 496. 

 Sacral ribs, 602. 

 Sacrum, 602. 

 Salivary glands, 305. 

 Scala tympani, 506. 



vestibuli, 506. 

 Scapula, 638. 

 Schizocoel, 108. 

 Sclerotica, 471 . 

 Sclerotome, 172, 348, 362. 

 Scrotum, 392, 402. 

 Sebaceous glands. 528. 

 Seessel's pocket, 594. 

 Segmental theory of skull, 631. 

 Segmentation see Cleavage. 

 Sella turcica, 438, 607. 

 Semicircular canals, bony, 503. 



membranous, 494. 

 Semilunar valves, 564. 

 Seminal ampullae, 383. 



mother-cells, 383. 



tubules, 384. 



see also Spermatic. 

 Septa placentas, 262. 

 Septum atriorum, 558. 



transversum, 567, 577. 



ventriculorum, 560. 



Sexual cords of the mesonephros, 381- 

 383, 404. 



eminence, 399. 



folds, 400. 



glands see Sexual organs. 



groove, 400. 



organs, 374. 



organs, external, 397. 



part of mesonephros, 387, 394. 



ridge, 399. 



Sheath of the root of hair, 525. 

 Shell of Hen's egg, 17. 

 Shell-membrane, 17. 

 Shoulder-blade, 638. 

 Shoulder-girdle, 638. 

 Sinus cervicalis (precervicalis), 289. 



coronarius, 565, 581. 



ethmoidales, 518. 



frontales, 518. 



genitalis, 396. 



occipitales, 518. 



prostaticus, 389. 



reunions, 558. 



sphenoidales, 518. 



superior of vertical semicircular 



canals, 496. 



terminalis, 184,549. 



urogenitalis, 398. 



