412 Proceedings of the Royal Irish Academy. 



decomposition had advanced too far, but always in an extremely 

 atrophic state. Those fibres, which go directly to the margin of the 

 epiglottis itself, have also been described under the name of musculus 

 epiglotUdis {reflector s. depressor epiglottidis .) 



Thyreo-epiglottiGu& longus (C. Krause). — This band of muscular fibres 

 I have found in two cases out of twenty-seven in which it was care- 

 fully sought for. Arising from inner surface of ala of thyroid cartilage, 

 immediately above the incisura thyreoidea inferior lateralis, it passes 

 upwards on the outer side of the thyreo-arytaenoideus, to be inserted 

 with the fibres of the thyreo-ary-epiglotticus into the corresponding 

 lateral margin of epiglottis. 



TJiyreoideus internus ; sub-thyreoideiis (Krause). — According to this 

 author, a muscular bundle may be found in from 15 to 20 per cent. 

 of all cases examined, passing from lower margin of ala of thyroid 

 cartilage, near the middle line, backwards to the posterior attachment 

 immediately above the root of the inferior cornu. I have found it 

 twice in forty-three bodies. 



Thyreoideus propriiis (Krause). — The name has been applied by 

 this author to a delicate layer of muscular fibres lying on the inner 

 surface of the thyroid cartilage, and reaching from the incisura superior 

 nearly to the inferior margin. In their descent they interlace with 

 the other internal muscles. I have in a few cases found a small num- 

 ber of scattered vertical fibres in this situation, but never so arranged 

 as to form a distinct layer. 



Syndesmo-thyreoideus. — This name has been appKed to a small 

 muscle found in very rare instances (one per cent, according to Krause) 

 passing from upper part of inner surface of thyroid cartilage to pos- 

 terior thyro-hyoid ligament. I have met with it twice : in one 

 subject it was symmetrically developed on both sides. 



Kerato-arytaenoideus {schildlcnorperhom-giesslecTcenhnorpels-mushel of 

 J, Gruber). — Arises from posterior border of inferior cornu of thyroid 

 cartilage, and is inserted into the muscular process of the arytaenoid. 

 I have found four examples. 



Other anomalous laryngeal muscles have been described by many 

 writers — such as the hyo-epiglottimis (Fabricius); crico-epiglotticics 

 (Verheyen) ; glosso-epiglotticus (Eustachius) ; but I have never met 

 with a specimen of any of them. 



Digastric. — The only noteworthy anomaly of this muscle I have 

 met with is a doubling of the anterior belly, the anomalous slip going 

 to the median raphe of the mylo-hyoid muscles. Once I have found 

 it symmetrical, the two supernumerary slips meeting in the mesial 

 line, and in three other cases the anomaly existed on one side only. 



Mento-hyoid (Macalister). — Of this muscle I have met with four 

 examples. In all it lay superficial to the anterior belly of digastric, as 

 it passed from front of body of hyoid bone to lower border of inferior 

 maxilla. In one instance it was symmetrically developed. 



Mylo-liyoideus. — The only remarkable variation I have seen in the 

 attachments or relations of this muscle was a perforation of the pos- 

 terior part by Wharton's duct, which came under my observation twice. 



